Every false religion including Islam, and every false gospel and Christian cult including Roman Catholicism, are debunked and destroyed by the allegory of Abraham's two sons, Ishmael and Isaac (if people would only read and understand the Bible). That allegory also distinguishes the true Gospel of Christ (salvation by grace through faith) from all false gospels of salvation by works. Hear Henry Mahan give a crisp and clear sermon on the story and its spiritual meaning, beginning in Genesis 17, where God tells Abraham "Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him. And as for Ishmael, I have heard thee: Behold, I have blessed him, and will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation. But my covenant will I establish with Isaac, which Sarah shall bear unto thee at this set time in the next year." (Gen. 17:19-21; https://www.biblegateway.com/passage/?search=Genesis+17&version=KJV); and ending in Genesis 21:10-12, "'Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, even with Isaac.' And the thing was very grievous in Abraham's sight because of his son. And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy bondwoman; in all that Sarah hath said unto thee, hearken unto her voice; for in Isaac shall thy seed be called." (https://www.biblegateway.com/passage/?search=Genesis%2021&version=KJV).

This allegory is partially expounded by the Apostle Paul in Galatians 4 where he teaches, "For it is written, that Abraham had two sons, the one by a bondmaid, the other by a freewoman. But he who was of the bondwoman was born after the flesh; but he of the freewoman was by promise. Which things are an allegory: for these are the two covenants; the one from the mount Sinai, which gendereth to bondage, which is Agar. For this Agar is mount Sinai in Arabia, and answereth to Jerusalem which now is, and is in bondage with her children. But Jerusalem which is above is free, which is the mother of us all. For it is written, Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not: for the desolate hath many more children than she which hath an husband...

...Now we, brethren, as Isaac was, are the children of promise. But as then he that was born after the flesh persecuted him that was born after the Spirit, even so it is now. Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman. So then, brethren, we are not children of the bondwoman, but of the free." (Gal. 4:22-31; https://www.biblegateway.com/passage/?search=Galatians%204&version=KJV).

After Paul's death, we see the rise of the Roman Catholic Church, Islam, and many other false religions which are nothing more than new attempts at the same old ploy to reinstate the child of the bondwoman: Ishmaels devised by deluded and deceitful men to oppose the true Gospel of salvation by grace through faith in the Lord Jesus Christ, false religions that claim there is a way to "earn" salvation by "doing" this and that or by "jihad" or "penance" or "observing the Jewish feast days" or "observing the Saturday sabbath" (SDA) and so on, ad nauseam. Most interestingly, Mohammed taught his followers that Abraham's son Ishmael was the true heir to God's covenant, even though the Bible clearly states that salvation would come through Isaac, who begat Jacob, who begat the twelve tribes, the fourth of which (Judah) begat Christ. Ishmael would become a strong nation as Abraham's son in the flesh, but would NOT be heir to the promise of God's everlasting covenant. Sorry, Muslims, you have been sorely deceived by your wicked false prophet, and you should have known better since you had the Bible available to you to read and confirm for yourselves what God really said to Abraham.

The same rebuke could be given to nominal Christians who have yet to replace all of their own righteousness with Christ's and Christ's alone. Original audio file and hundreds more sermons from Henry Mahan are available for free on sermonaudio.com here: http://www.sermonaudio.com/sermoninfo.asp?SID=22406104936

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