If a being capable of suffering is generated from a biological system, the loss of energy in that system needs to be replaced. It has to eat. The way we eat is by destroying other beings, some capable of suffering. It's necessary. But let's clean it up. Let's assume we could somehow get by with air and light, entirely things devoid of suffering. Cell replication degrades, but then let's assume it doesn't. Then the tragedy is postponed, but not forever. Entropy will catch you with the sun, and that's assuming vastly good fortune. Heaven/hell/the perpetual/the eternal/the perpetually cyclical - all require either input from outside the concept, or a form on encapsulated stasis of perfect recyclical efficiency.