"Odin gave his eye to acquire knowledge, but I would give far more."
Vikings 1.01 (Rites of Passage)
"It is always a strength to know the weaknesses of your friends, is it not?" (Vikings, 02x02)
Athelstan is driven at the start of season two by this whole conflict between Christianity and Paganism, and his day-to-day choices are still very much defined by this internal conflict.
"It is one thing to use a weapon, but another to kill. Never hesitate." x
"I am giving you a choice, Rollo. Go and speak with your brother, or take this blade, push it into your ribs right now. Stay in hell for all eternity."