Giovanni 1:18

No man hath seen God at any time; the only begotten Son, which is in the bosom of the Father, he hath declared him. No man hath seen God at any time - Moses and others heard his voice, and saw the cloud and the fire, which were the symbols of his presence; but such a manifestation of God as had now taken place, in the person of Jesus Christ, had never before been exhibited to the world. It is likely that the word seen, here, is put for known, as in Giovanni 3:32; 1 Giovanni 3:2, 1 Giovanni 3:6, and 3 Giovanni 1:11; and this sense the latter clause of the verse seems to require: - No man, how highly soever favored, hath fully known God, at any time, in any nation or age; the only begotten Son, (see on Giovanni 1:14 (note)), who is in the bosom of the Father, who was intimately acquainted with all the counsels of the Most High, he hath declared him, εξηγησατο, hath announced the Divine oracles unto men; for in this sense the word is used by the best Greek writers. See Kypke in loco.

Lying in the bosom, is spoken of in reference to the Asiatic custom of reclining while at meals; the person who was next the other was said to lie in his bosom; and he who had this place in reference to the master of the feast was supposed to share his peculiar regards, and so be in a state of the utmost favor and intimacy with him.