I think obeying what Jesus commands us to do is showing that we believe in Him.
James would say faith without works (deeds, actions) is dead. He is showing his faith by his works. He gave examples like if someone comes to you in rags do you just tell them to sit faaaaar away from you. Or do you give him some new clothes to wear? Or if someone comes to you and they are wearing fine clothes do you treat them much better than anyone else?
Stuff like that. GOd is no respector of persons. He sees into peoples hearts, remember he can even see when we try and cover ourselves up. He saw adam and eve in the garden trying to hide from Him.
I agree in that if we LOVE the Lord Jesus Christ then doing as He told us comes easy. However...…….that does not have anything to do with salvation at all in any way whatsoever.
We are saved 100%....totally and completely by what Jesus did for us on the cross. There is nothing to add to that event.
Should you want to give someone your cloths who has none...YES. But not because it effects your salvation. You do it because it is the right thing to do as a Christian who is in love with Christ.