Self-righteousness is the big lie of Satan. The truth is you are saved by Christ; the lie is you are saved by anything other than Christ. That lie can come in all kinds of packages: You can be saved by following these rules, doing these routines, belonging to this or that system, being good enough to outweigh your shortcomings…there’s a myriad of possible systems to counter the one truth, and they are all part of Satan’s big lie. If Satan can get somebody into a system that says they are righteous, it’s very hard to extract them from it. One reason is that self- righteousness is very proud. I am reminded of what Job said to those who judged him: “No doubt but ye are the people, and wisdom shall die with you” (12:2). Proverbs 12:15 says, “The way of a fool is right in his own eyes….” Luke 16:15 says, “…that which is highly esteemed among men is abomination in the sight of God.” When men believe Satan’s lie and develop a system that is highly esteemed in their eyes, it is an abomination to God. Salvation can never be earned by good works and keeping religious rituals.
– John MacArthur