ἄφθαρτος is properly incorruptible, unaffected by corruption and decay. It is applied to God, and to that which is connected with him. ἀμάραντος expresses the same idea in another way. It means unfading, the root idea being that it is unaffected by the withering which is common in the case of flowers. ἀμαράντινος, derived from ἀμάραντος, means composed of amaranths, i.e., of unfading flowers.