John 1:18

and though no one hath ever seen God, or can see Him: yet the only-begotten Son, who is in the bosom of the Father, hath made Him known.

John 12:41

These things said Esaias when he saw his glory, and spake concerning Him.

Treasury of Scripture Knowledge

Summary

And when Gideon perceived that he was an angel of the LORD, Gideon said, Alas, O Lord GOD! for because I have seen an angel of the LORD face to face.

Bible References

Because

John 1:18
and though no one hath ever seen God, or can see Him: yet the only-begotten Son, who is in the bosom of the Father, hath made Him known.
John 12:41
These things said Esaias when he saw his glory, and spake concerning Him.