Mahanama asked the Buddha a question a typical puthujjana would ask. Namely, "what will happen when I die or what will happen after my death"? The Buddha did not answer his question by saying "Have no fear, Mahanama! Have no fear! Your rebirth will not be a bad one". He merely said "Have no fear, Mahanama! Have no fear! Your death will not be a bad one". maranam means death. kalakriya means death. As I see it, he was merely speaking of the experience of death; not after-death.