Hebrews 13:2

Forget not to show love unto strangers: for thereby some have entertained angels unawares.

This might be a reference to the conduct of Abraham and Lot who granted open and ready hospitality to certain strangers who proved to be not men at all, but angels (Genesis 18:1; Genesis 19:1). This verse teaches that men given to hospitality toward strangers will, at times, entertain persons who are in every way a blessing and honor to the host. It may seem at first that this is a low motive for hospitality; but, as Young noted:

If it be considered, we shall see that it is not so much a motive to hospitality as to unremitting watchfulness in hospitality. Let the stranger be ever in your mind. Let no one slip by your gates, or go away knocking in vain. What will it avail to admit a thousand who bring you nothing but their needs, if you let one go who will bring you blessings far more than anything you can do for him?[1]

In Bardstown, Kentucky, a Catholic priest granted hospitality to a stranger who stayed for several months. The stranger made no effort to contribute anything to that wilderness parish; and when he left, he gave only his thanks. Some years afterward, a great shipment of some of the world's most beautiful paintings arrived at the little church, where they were lovingly received and exhibited, and where thousands of people touring the United States still pause and enter to view them every year. That stranger was a prince of France in exile; and when he returned to that land, one of his first acts was to send a royal gift to the parish priest of Bardstown.<1a> The true king, Christ himself, in the person of his disciples, is often the seeker of hospitality at the hands of Christians; and, although the duty of hospitality is one of the most exacting and difficult requirements of the Christian life, it should be exercised faithfully in respect of the commandment of God, and in the framework of another of the divine laws that Christians should be "as wise as serpents and as harmless as doves" (Matthew 10:16).

[1] D. Young, The Pulpit Commentary (Grand Rapids, Michigan: Wm. B. Eerdmans Publishing Company, 1962), Vol. 21, Hebrews, p. 415.

<1a> Prince Louis Philippe of France spent a part of his exile at Bardstown about 1800.