John 6:66

From that [time] many of his disciples went back,.... Not any of the twelve apostles, for they are distinguished from these in the next verse; nor any of the seventy disciples, for their names were written in heaven, and could not apostatize totally and finally, as these did; but some of the multitude of the disciples, who followed Christ, heard him, and professed to believe in him, and were baptized in his name, but were not true disciples, only nominal ones: they had never heard and learned of the Father, otherwise they would have known what it was to come to Christ, as the Father's gift, and under the drawings of his grace; and would not have been offended at the words of our Lord, just now spoken by him, concerning that sort of coming to him: but from the time he spoke those words; "because of this word", as the Syriac, Arabic, and Persic versions render it; they withdrew themselves from his ministry, they dropped their profession of faith in him, and relinquished him as a Saviour and Redeemer: for finding that he would not be made king, nor set up for a temporal redeemer; and talking of himself as the bread of life, and of coming to him, in a sense they did not understand; they turned their backs on him; and as the words may be literally read, "returned to the things that were behind"; to the world, and to their old companions, to Satan and their own hearts lusts; like the dog to its vomit, and the swine to its wallowing in the mire: their true picture is drawn, in the parable of the unclean spirit going out of the man, and returning, Mt 12:43.