William Burkitt on John 6:41

Although Christ had in the foregoing verses plainly asserted himself to be the true bread that came down from heaven, for the benefit of the world; yet the Jews understanding his words carnally, are offended with him, for pretending to come down from heaven, when they knew him to be the son of Joseph and Mary. They understood nothing of his divine nature, nor of his miraculous conception by the over-shadowing of the Holy Ghost, and therefore were highly offended at him.

Thence learn, That ignorance of Christ's divine nature was the ground and occasion of that contempt which was cast upon his person.

Observe farther, The proof which Christ gave of his divine nature, in his knowing the hearts and thoughts of these murmuring Jews; Jesus said, Murmur not among yourselves. Christ knows and observes the most secret murmurings and repinings that are found in the breasts of the children of men: and this his knowledge is an evidence and proof of his divinity, that he is truly and really God.