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 And whether We show you part of what We promise them or take you in death, upon you is only the [duty of] notification, and upon Us is the account. 40 Have, then, they [who deny the truth] never yet seen how We visit the earth [with Our punishment,] gradually depriving it of all that is best thereon? For, [when] God judges, there is no power that could repel His judgment: and swift in reckoning is He! 41 Now those who lived before these [sinners] did, too, devise many a blasphemy - but the most subtle devising is that of God, who knows what each human being deserves: and the deniers of the truth will [in time] come to know to whom the future belongs. 42 The unbelievers say, 'Thou art not an Envoy.' Say: 'God suffices as a witness between me and you, and whosoever possesses knowledge of the Book.' 43