John Calvin on John 6:46

46. Not that any man hath seen the Father. As he has hitherto magnified the grace of his Father, so now he earnestly directs believers to himself alone. For both must be joined together; that no knowledge of Christ can be obtained, until the Father enlighten by his Spirit those who are by nature blind; and yet that it is in vain to seek God, unless Christ go before; for the majesty of God is so lofty, that the senses of men cannot reach him. Nay, more, all that knowledge of God which men may think that they have attained out of Christ will be a deadly abyss. When he says that he alone hath known the Father, he means that it is an office which belongs peculiarly to himself, to manifest God to men, who would otherwise have been concealed.