No one who has once understood what the Christian life means can ever be the same again. Either he will be the better for his knowledge, or else he will be worse. His life cannot possibly be lived on the same original plane of spiritual experience. If, by means of this knowledge, we obtain ideals, and do not at once set to work to realize them, both the ideal and the real will be lowered from this time forward. Hence the importance, the necessity, of taking heed to such a message as that which was given by our Lord to His disciples: “If ye know these things, happy are ye if ye do them” (John 13:17). I. The Christian life starts with knowledge. “If ye know these things.” It is absolutely essential that we should “know” these things. A knowledge of Christian truth is of paramount importance, of primary necessity. It does matter what we believe. Knowledge is ever one of the springs and sources of action. “Conduct,” as Matthew Arnold says, may be “three-fourths of life,” but the other fourth is the motive power of the three. A train is much longer than the engine, but the engine provides the motive power. A building is much larger than the foundation, but the foundation is very necessary. A tree is much wider than the root, but it is the root which gives life to the tree. Knowledge is absolutely necessary. It is necessary in the Christian life for protection. If we knew more, we should be preserved from error on this or that side. In the later Epistles of St. Paul, in which we have the mature spiritual experience of the Apostle, we find a strong emphasis upon “knowledge,” and in almost every case the word so rendered means mature, ripe knowledge. These Epistles are full of the thought of knowledge as the mark of a growing Christian, a ripening spiritual perception, a deepening knowledge of God’s truth. And in the still later Epistles, the Pastorals, we have the phrase again and again, “sound doctrine,” not so much in the sense of intellectual clearness, as of healthful doctrine, that which ministers to spiritual health. In the last Epistle of St. Peter (which consists of only three chapters) we have, again, this thought of mature knowledge. In almost every case in which the word occurs in those chapters it is a rendering of the word “epignosis,” and at last the Epistle closes with “Grow in grace, and in the knowledge of our Lord and Saviour.” Then, again, in that Epistle of St. John which we call the First Epistle, the keynote is “that ye may know.” Knowledge will keep us from error of all kinds. A clear conception and perception of Christian truth will be our greatest protection. It is worthwhile to notice the three stages of the Christian life mentioned in the Epistle of St. John (2:12–14). The little children are those who have; the young men are those who are, and the fathers are those who know. Not only for protection, but also for peace, knowledge is necessary. “I know whom I have believed, and am persuaded that He is able to keep that which I have committed to Him against that day.” That is the expression of the experience of a man who knows: “If ye know these things.” As we look back over our past life, we may think of the things that we have read, understood and learned. Every one of us has something to be included in this phrase, “If ye know these things.” But it so happens that there are, at least, five “things” in the immediate context which are essential elements in our knowledge. The first is, “He that has been bathed,” he that has received the bath of a perfect justification. This is, as we have seen, at the root and foundation of all Christian living. We must have “the Lord our righteousness” for justification. Secondly, a perpetual cleansing. “If I wash thee not.” “Ye are clean, but not all.” This is one of the “these things” enforced in Scripture, – perpetual cleansing in and through the Lord Jesus Christ. Then, loyal submission. “Ye call Me Teacher and Lord, and ye say well, for so I am. If I then, your Lord and Teacher.” Notice those two titles, Teacher and Lord. In the order of our experience it is “Teacher and Lord”; but in the order of His purpose it is what He Himself claims – “Lord and Teacher”. We have been learning of Him as our Teacher, and what it is to call Him Lord. “To this end Christ both died, and rose, and revived, that He might be Lord.” Next, a lowly spirit. The Lord “girded Himself” and took the place of a servant, though filled with a Divine consciousness as in verse three: “Knowing ... that He was come from God, and was nevertheless going to God; He ... took a towel and girded Himself.” In the very height of His Divine consciousness, He stooped to the position of lowliness. And whenever we have been on the mountain top and had a glimpse of Divine things, it is that we should have the same spirit of lowliness. Fifthly, social service. He not only took the position, but did the work of a servant in washing the disciples’ feet. “If ye know these things.” Do we know them? For it cannot be too often emphasized that knowledge in the New Testament is not merely intellectual perception; it is spiritual experience. Do we know these things? Do we know all of these five? Do we know what it is to have Christ for our perfect justification? Do we know what it is to have Him as our continual sanctification? Do we know what it is to know Him as our Lord and Master and Teacher? Do we know what it is to have Him as our pattern of lowliness and service? Do we know these things? “Christ for us our atoning sacrifice, Christ in us our living power, Christ under us our sure foundation, Christ around us our wall of fire, Christ beside us our perfect pattern, Christ over us our blessed Master, Christ before us our everlasting heritage.” “If ye know these things.” II. The Christian life proceeds to action. “If ye know these things, ... do them.” Christianity is not a creed alone; it is a life. If knowledge is the spring of action, action is the end of knowledge. There are two words in the New Testament which practically sum up all that is contained in the phrase “do them,” “walk” and “work”. These may be stated as character and conduct; holiness and service. The “walk” comes first. We recall the frequency with which the word “walk” is used to express the activity and progress of the Christian life. Sometimes we find it in connection with sincerity; we are to walk before God (Gen. 17:1). Sometimes in connection with obedience; we are to walk after Him (Deut. 13:4). Sometimes in connection with union; we are to walk in Him (Col. 2:10). Sometimes in connection with fellowship; we are to walk with Him (Mal. 2:6). Perhaps this metaphor is used because walking is one of the three perfect forms of exercise, in which every faculty and power of our physical being are brought into play. There are forms of exercise quite as enjoyable, which do not do this, but walking, running and swimming do. The “walk” of the Christian life is intended to bring out every faculty of our spiritual being. By “doing these things” we start with the act, and then go on to habit and character. Many of us recall the teaching of Butler about passive impressions and active habits. We continually receive impressions; but if these passive impressions are not at once transformed into acts of the will, in order that they may become habits, then the impressions will have been in vain. If we are not already putting into practice in our wills, in our inmost being, what we know, we are already losing it. And it is just here that many of us fail in the Christian life, and fail again and again. Is it not simply terrible to think of failure when we might be going forward? Why is it terrible? Because if only we would at once translate, by means of the will, the impression which we receive, we should get an influx of power, and from the act would come a habit, and instead of our life being a series of intermittent acts, the acts would be joined to one another, and this would not mean merely a chain but an ever-stronger chain, one perfect line, forming at last the habit of our life. Then prayer would become easy, meditation on the Bible easy, making time for prayer and the Bible easy, surrender easy, obedience easy, because of the habit, the walk of life. There is something instinctive in the movement of the arm, or even of the body, in walking; and what that is in things physical, our spiritual life is intended to be, that we may be “stablished, strengthened, settled”. And then will come work. Not merely character, but conduct; not only holiness, but service. Our Lord did something; He washed His disciples’ feet, He served them in that moment of exalted consciousness. And if we do not entertain the determination to work our profession will be in vain. We have spiritual and social work to do. Wherever our life is treated in the New Testament we always find three aspects: eternal, internal, external, – our relation to God, our relation to ourselves, and our relation to others. The fruit of the Spirit is ninefold, – three with regard to God, three with regard to our fellows, and three with regard to ourselves (Gal. 5). The threefold aspect of St. John’s First Epistle is clear and includes obedience to God, love to the brethren, and the possession of the Holy Spirit in the heart. When Paul preached to Festus, he preached righteousness, self-control, and judgment to come – our threefold relationship. And so when we have been dealing with God, it is in order that there may go forth from us to others the influence and power of a holy life and holy character in blessed and loving service. There is, first of all, the home circle, and that may be, for some of us, the most difficult; but it must be faced. We have to “show piety at home.” Let us, however, take care that the difficulties are not of our own making. Let the youngest of us remember that in the home life we are not infallible, even after we have had spiritual enlightenment. And we must see that those who are older than ourselves are not able to say, “Well, if that is what Christian living means, I do not feel drawn to it.” We read in our Lord’s life that “the house was filled with the odor of the ointment.” So let it be with us in things spiritual. Then comes our church life. If we are in the ministry, we shall realize what the work of the ministry means in the light of the New Testament. But whether minister or layman, our work will mean devoted service for God, and loving and loyal service one for another, washing the disciples’ feet. This is what we have to face. Somewhat quaintly, but very truly, three rules have been given for washing the disciples’ feet. First, “the water must not be too hot.” There is a danger of censoriousness, a serious risk of censoriousness in relation to others; and if we scold, we shall scald, and that will be fatal. Secondly, “our own hands must be clean while we do it.” If our hands are not clean when doing this work of washing the feet of others, this work of loving service, we shall not do our duty to our Master. Thirdly, “we must be quite willing for others to wash our feet.” This involves a good deal of humility. When these things are true, we shall have the true home and the true church life. But it is necessary to look wider, and to think not merely of the home life and of the church life, but also of the national life. It is sometimes said that many Christians are indifferent to the thousand and one evils of the present day. Nothing could be more unfair than that charge. It cannot be forgotten that redemption and regeneration are never applied to society or the New Testament, but only to the individual in regard to his spiritual needs; and the Gospel is primarily salvation, not civilization. But with this realized and kept in front, the Gospel is to be applied to all life. It is our bounden duty to apply the Gospel to all the social ills of today. We face these social problems and bring to bear upon them the teaching of the New Testament. Nothing in this world can deal so quickly or so effectively with our social evils as the old-fashioned evangelical verities of the New Testament. The problem of the unemployed can only be solved by Christian men and women, as also the problem of poverty, the problem of pauperization, the problem of the drink traffic, the problem of gambling, the problem of impurity, the problem of the desecration of the Lord’s Day, and the problem of war. Not least of all is the problem of the use of money. Systematic and proportionate giving as the great New Testament principle ought to be applied by every one of us in every action of our life, in order that it may be seen that we are not forgetful of the social claims of others. And let us not forget, in this connection, that the Lord Jesus Christ does not look upon what we give, but upon what we have left after we have given. Let us recall that whilst the Lord looked upon that widow’s two mites (not one mite) He looked upon it because she had nothing left to give. When social problems are thus faced, none of them will prove insoluble. But it is necessary to look wider still and think of the universal life, “If ye know these things, happy are ye if ye do them.” There is an application to evangelization. The home, the church, the nation, the world. This is in the line of God’s will, and the Christian who puts worldwide evangelization in the proper place in his life, – the first place, God’s place, will find in it the key to everything in the home, in the parish, in the nation. “If ye know these things, ... do them.” III. The Christian life culminates in blessedness: “If ye know these things, blessed are ye if ye do them.” We shall know by experience the blessedness of holiness. This will involve the blessedness of spiritual peace, the blessedness of spiritual power, the blessedness of spiritual provision, the blessedness of spiritual permanence, the blessedness of “abiding,” “stablished, strengthened, settled.” The joy of the Lord will be deep as we know Him as our righteousness for justification, our righteousness for sanctification, our righteousness for consecration. Then there will be the blessedness of service! Is there any blessedness comparable with the blessedness of love? A man once went to his minister and asked him to tell him something about heaven, and the minister said, “Down the street is a widow with some small children. Go to the grocer, – do not send but go; buy what you can from that grocer’s shop; then go to the baker, then to the greengrocer, and then take the things yourself, give them to this widow and pray with her.” The man did so, and in a little time he came back and said, “Pastor, I do not need to know anything now about heaven; I’ve been there!” He had realized something of the joy, the unspeakable joy of love! That is heaven; for “God is love.” And not least will come the blessedness of obedience. It will be the blessedness of putting into practice what we know, and it fills the soul with the peace of God in an ever-increasing degree. And so we rejoice in the blessedness of work. Work will no longer be a toil and a moil, but a joy; no longer a weariness, but a delight. There is a hymn that we sometimes sing, “I’ve found a Friend,” and it seems somewhat selfish, though we do not mean it for selfishness, when we sing those words in it: “And now to work, to watch, to war, And then to rest forever.” Would it not be better to sing, “And now to work, to watch, to war, And then to work forever.” It is of course true that “they rest from their labours,” but it is also true that “they rest not day nor night”; and to every healthy, vigorous Christian work is and ever will be the joy and delight of life. And what can we say of the blessedness of influence? This is the blessedness of realizing, in however small a degree, and to however little an extent, the influence that is holy as it flows out from us to others. Some years ago a lady was walking home from the station about midnight after speaking at a large meeting in London. As she neared her home, she thought she saw someone leaning against the wall, near the gateway of her house. She found that it was a young girl, and very soon saw that the girl was ill. She took her in that night, gave her a bed and everything possible for her comfort. The next morning she made arrangements for the girl to be taken to a suitable home where her needs would be attended to. But the end was very near. They telegraphed soon afterwards to the lady to come and see her. When she leaned over the bed to speak to the girl and spoke to her about better things, this is what the girl said: “I have not found it hard to think about God since I saw you!” Is there anything in this world higher than that – that people should not think it hard to think about God by reason of our life? “I have not found it hard to think about God since I saw you.” “Blessed are ye if ye do them.” That is the life to which God is calling us, the life in the home, in the church, in the nation, in the world. “Therefore, my beloved brethren, be ye steadfast, unmovable, always abounding in the work of the Lord, forasmuch as ye know that your labour is not in vain in the Lord.”