Charles Ellicott Commentary John 6:46

"Not that any man hath seen the Father, save he that is from God, he hath seen the Father." — John 6:46 (ASV)

But this hearing and learning of the Father was the preparation for, not the substitute for, the fuller revelation in the person of the Son. Once again He declares that “No man hath seen God at any time; the only begotten Son which is in the bosom of the Father, He hath been the interpreter.” (See Note on John 1:18; and compare to John 3:13; John 8:38.) Every man, in proportion as he had been taught of God, would feel how little he knew of God, and there would be in him the yearning desire and the trained faculty to see Him who is of God.