Adam Clarke's Commentary on the Bible - John 6:59
In the synagogue - in Capernaum - From John 6:26 , to this verse, the evangelist gives us the discourse which our Lord preached in the synagogue, in which he was repeatedly interrupted by the Jews; but this gave him the fuller opportunity to proclaim the whole truth relative to his passion and death, to edify the disciples, and confute these gainsayers. read more
John Gills Exposition of the Bible Commentary - 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... read more