It is in James where this statement occurs (which appears to contradict Paul's teachings about faith, e.g., Rom 3:28)
'So faith by itself, if it has no works, is dead' (James 2:17).
It is obvious by what the author says that 'works' are deeds that are related to kind behaviour and not specifically with a 'religious' association (e.g., attending meetings, witnessing, etc) . This is made clear in say, 2:15-16 and certainly in 1:27: 'Visit orphans and widows in their affliction, and to keep oneself unstained from the world'. Also to oppose or at least ignore wealth and capitalism (2:2-6).
If all Bible-believers followed what James says, the world would be a happier place. Instead of all the religious preaching they would have to care for the afflicted (and not only their own, but those of different faiths and groups - Matt 5:46-47).
Just as note: Witnesses I have spoken to say that the demand that they dress up in smart suits (like insurance salesmen) for meetings is what Jehovah wants as they are his representatives and yet James 2:2-4 surely does not support this.