2 Timothy 2:15 says:
15Do the very best you can to be the kind of person that God will accept, and give yourself to him. Be a worker who is not ashamed of his work--a worker who uses the true teaching in the right way. (Easy-to-Read Version)
King James Version: 15Study to shew thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth.