The New Testament contains two often-compared passages: Paul writes in Ephesians 2:8-9 that salvation is by grace through faith and "not of works," and James writes in James 2 that a faith without works is "dead."
James 2:17-18 in the King James Version reads:
17 Even so faith, if it hath not works, is dead, being alone. 18 Yea, a man may say, Thou hast faith, and I have works: shew me thy faith without thy works, and I will shew thee my faith by my works.
These verses appear in James 2, in a passage that repeatedly pairs the words "faith" and "works." Read it in context at James 2:17-18, or the full chapter at James 2. See also Ephesians 2:8-9. Encyclopedia entry: en.wikipedia.org/wiki/Faith_and_works_in_Christianity.