The ungodly don’t understand that their sin is against God (see Psa. 51). They believe certain sinful actions are morally acceptable “as long as they don’t hurt anyone.” But all sin offends God. The true convert understands that he has transgressed against a holy God (see also 3:13).
Jeremiah 2:29 “Why will you plead with Me? You all have transgressed against Me,” says the Lord.