Albert Barnes Commentary John 6:15

"Jesus therefore perceiving that they were about to come and take him by force, to make him king, withdrew again into the mountain himself alone." — John 6:15 (ASV)

When Jesus perceived, etc. They were satisfied by the miracle that he was the Messiah. They supposed that the Messiah was to be a temporal prince. They saw that Jesus was retiring, unambitious, and unwilling to assume the ensigns of office. They thought, therefore, that they would proclaim him as the long-expected king, and constrain him to assume the character and titles of an earthly prince.

People often attempt to dictate to God, and suppose that they understand what is right better than he does.

They are fond of pomp and power, but Jesus sought retirement, and displayed profound humility. Though he had claims to the honour and gratitude of the nation, yet he did not seek it in this way; nor did it display a proper spirit in his followers when they sought to advance him to a place of external splendour and regal authority.