Galatians 5:21

21.Of which I tell you before. By this awful threatening he intended not only to alarm the Galatians, but likewise to glance indirectly at the false apostles, who had laid aside the far more valuable instruction, and spent their time in disputing about ceremonies. He instructs us, by his example, to press those exhortations and threatenings, agreeably to the words of the prophet,

“Cry aloud, spare not; proclaim to my people their sins.”
(Isaiah 58:1)

What can be conceived more dreadful than that men should walk after the flesh, and shut themselves out from the kingdom of God? Who will dare to treat lightly the “abominable things which God hates?” (Jeremiah 44:4.)

But in this way, we shall be told, all are cut off from the hope of salvation; for who is there that is not chargeable with some of those sins? I reply, Paul does not threaten that all who have sinned, but that all who remain impenitent, shall be excluded from the kingdom of God. The saints themselves often fall into grievous sins, but they return to the path of righteousness, “that which they do they allow not,” (Romans 7:15,) and therefore they are not included in this catalogue. All threatenings of the judgments of God call us to repentance. They are accompanied by a promise that those who repent will obtain forgiveness; but if we continue obstinate, they remain as a testimony from heaven against us.

They who do such things shall not inherit the kingdom of God. The word κληρονομεῖν signifies to possess by hereditary right; for by no right but that of adoption, as we have seen in other passages, do we obtain eternal life.