These verses form a sorrowful conclusion to the famous discourse of Christ which occupies the greater part of the sixth chapter. They supply a melancholy proof of the hardness and corruption of man’s heart. Even when the Son of God was the preacher, many seem to have heard in vain.
Let us mark, in this passage, what an old sin backsliding is. We read that when our Lord had explained what He meant by “eating and drinking His flesh and blood,” “From that time many went back and walked no more with Him.”
The true grace of God no doubt is an everlasting possession. From this men never fall away entirely, when they have once received it. “The foundation of God standeth sure.” “My sheep shall never perish.” (2 Tim. 2:19; John 10:28) But there is counterfeit grace and unreal religion in the Church, wherever there is true; and from counterfeit grace thousands may and do fall away. Like the stony ground hearers, in the parable of the sower, many “have no root in themselves, and so in time of temptation fall away.” All is not gold that glitters. All blossoms do not come to fruit. All are not Israel which are called Israel. Men may have feelings, desires, convictions, resolutions, hopes, joys, sorrows in religion, and yet never have the grace of God. They may run well for a season, and bid fair to reach heaven, and yet break down entirely after a time, go back to the world, and end like Demas, Judas Iscariot, and Lot’s wife.