“Faith apart from works is dead” (James 2:26)
James labels faith, without works, useless in verse 20, and in verse 22 he says that faith is completed by works. This is what he means. Living a life of obedience to God (as he says in chapter 1, both hearing and heeding the Word of God), is not an optional add-on to the life of faith. It’s not some second stage of Christianity that you eventually graduate into (“For now, I’ll just stick with being vaguely associated with Christianity and the church, but later I’ll get serious about it”). James says that’s like deciding to jump only to the halfway point across the Grand Canyon. He gives us a good word to describe the result: dead!