A verse very similar to 1 Corinthians 8:6 is Romans 11:36
For who hath known the mind of the Lord? [NWT "Jehovah"] or who hath been his counsellor?or who hath first given to him, and it shall be recompensed unto him again? For of him, and through him, and unto him, are all things. To him `be' the glory for ever. Amen. Romans 11:34-36 ASV
Comment: All things are "of" the Lord Jehovah and "through" the Lord Jehovah
"yet to us there is one God, the Father, of whom are all things, and we unto him; and one Lord, Jesus Christ, through whom are all things, and we through him." 1 Corinthians 8:6 ASV
Comment: All things are "of" the Father and "through" the Son. Hense the Father and the Son must both be the Jehovah "of" whom and "through" whom all things were made.