Question about Saint of Killers (Preacher)

Everyone knows the famous scene where he is at ground zero of a nuclear explosion, but simply shrugs it off and remarks 'Not enough gun'.

However, does this imply that it is possible to have 'enough gun' to kill him?

yes. but the only 'gun' big enough was God's hand when he was on the throne of power.

no earthly weapon could harm him