en_tn_condensed/gal/01/20.md

before God

Paul wants the Galatians to understand that Paul is completely serious and that he knows that God hears what he says and will judge him if he does not tell the truth.

In what I write to you, I assure you before God, that I am not lying

Paul uses litotes to emphasize that he is telling the truth. Alternate translation: "I am not lying to you in the messages I write to you" or "in the things I write to you I am telling you the truth" (See: rc://en/ta/man/translate/figs-litotes)