Faith grasps the divine promise of power to act righteously.
BUT, since none of us are perfect in faith short of “the day of Christ Jesus” its expression won’t be perfect either.
Ergo, sinning is possible. The only sin not possible, in fact, is the sin of refusing to accept the promise of salvation. Because that sin has been obviated.
Jesus can round ‘em up and head ‘em out like the best of sheep herders. You want to brag on your flesh. No will accommodate, and God will show you foolish. Weren’t you the one that made an obscene comment the other day? Not unforgivable, but it does break up your shiny image.