Does God speak and not act? Even Balaam understood that when God's Word goes forth, it accomplishes what He sent it to do. There is no ambiguity on this matter; God's promises are sure. He never deceives, and there is never inconsistency or fickleness in Him. He is always true. Jesus called Himself "the truth" (John 14:6), and in Revelation 3:14 His title is "the faithful and true witness."
Similarly, Paul states that his, Silvanus' and Timothy's declarations, their preaching about God, were also faithful, unvarnished, unexaggerated, and uncolored. They did not change the truth or shade it in any way. Jesus says He came into this world to bear witness to the truth (John 18:37). Paul felt he was under sacred obligation to do the same and maintain a character of the strictest veracity in every respect. Perhaps our greatest obligation on earth is for us to imitate our Redeemer's faithfulness. It does not become an individual who professes to trust in the faithful God to be shifty and unreliable in word and deed.
This is a very high pinnacle for us to strive for, but we must try, though we know we will not be saved as a result. Perhaps because we know our salvation does not depend on our works, there is a subtle persuasion not to be as careful as we should.