And We sent Messengers before thee, and We assigned to them wives, and seed; and it was not for any Messengers to bring a sign, but by God's leave. Every term has a Book. 38 God annuls or confirms whatever He wills [of His earlier messages] - for with Him is the source of all revelation. 39 BUT WHETHER We let thee see [in thy lifetime, O Prophet, the fulfilment of] some of what We have promised them, or whether We cause thee to die [before its fulfilment] - thy duty is no more than to deliver the message; and the reckoning is Ours. 40 Have they not considered that We have taken over the land and reduced its borders? It is God who issues the irreversible decree and His reckoning is swift. 41 Those before them did (also) devise plots; but in all things the master-planning is Allah's He knoweth the doings of every soul: and soon will the Unbelievers know who gets home in the end. 42 And those who disbelieve say: thou art not a sent one. Say thou: Allah is a sufficient witness between me and you, and also he with whom is knowledge of the Book. 43