Islam is a religion based upon reason; its teachings, therefore, have been presented in such reasonable proofs that every pure nature may understand them. One of the proofs has been mentioned as khairon wa abqa “Better and more lasting”. The reasoning leads man to an important decision when deciding to choose one of the two worlds of earthly or everlasting worlds. This proof is of four elements including meeting contradicted conditions, assessment of the conditions, distinguishing durable good from transient bad and preferring and choosing the former and leaving the latter. It should be stated that the proof has been founded on theological, cosmological and anthropological principles.