And verily We sent messengers (to mankind) before thee, and We appointed for them wives and offspring, and it was not (given) to any messenger that he should bring a portent save by Allah's leave. For everything there is a time prescribed. 38 God annuls or confirms whatever He wills [of His earlier messages] - for with Him is the source of all revelation. 39 (O Prophet), whether We make you see a part of the punishment that We have threatened them with come to pass during your life-time, or We take you away before that happens, your duty is no more than to convey the Message, and it is for Us to make a reckoning. 40 Do they not see that We are bringing destruction upon the land by curtailing it of its sides? And Allah pronounces a doom-- there is no repeller of His decree, and He is swift to take account. 41 Those who lived before them also devised many a plot, but the master plot rests with Allah. He knows what everyone does. The deniers of the truth will soon come to know whose end is good. 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