For we are not as many, which corrupt the word of God: but as of sincerity, but as of God, in the sight of God speak we in Christ.
Not as many (2 Corinthians 11:13-18; Philippians 2:21) - rather, 'the many;' namely, the false teachers (2 Corinthians 10:1-18; 2 Corinthians 12:1-21; 1 Thessalonians 2:3). Which corrupt, х kapeeleuontes (G2585)] - 'adulterating, as hucksters do wine for gain' (2 Corinthians 4:2; Isaiah 1:22; 2 Peter 2:3).
As of sincerity, but as of God - as becomes one speaking from (out of) sincerity, as from (i:e., with a mission and spiritual life emanating from) God the Father.
In the sight of God - the Holy Spirit, who hovers over the Church, witnessing and guiding its movements ['Aleph (') A B C read katenanti (G2713) for katenoopion (G2714)]. The Trinity is here (cf. Romans 11:36).
In Christ - united to Him in living membership (cf. 2 Corinthians 12:19). The whole Gospel must be delivered as it is, without concession to men's corruptions, without selfish aims, if it is to be blessed with success (Acts 20:27).