What is the theme in Sir Gawain and the Green Knight, Pearl, and Sir Orfeo by J.R.R. Tolkien?

God's grace is the primary theme of Pearl, but it is reflected in part in Sir Gawain and the Green Knight. God's grace is seen as a primary factor in leading Sir Gawain through his trials unharmed. Gawain prays at Mass to be protected from the Green Knight's axe and he believes that he is spared from harm from the Green Knight through God's favor. He also knows that when he repents God's grace it allows him to be forgiven.