The Unbelievers say: "Why is not a sign sent down to him from his Lord?" Say: "Truly Allah leaveth, to stray, whom He will; But He guideth to Himself those who turn to Him in penitence,- 27 Those who believe and find peace in their hearts from the contemplation of God: Surely there is peace of heart in the contemplation of God!" 28 Those who believe and do right: Joy is for them, and bliss (their) journey's end. 29 Thus have We raised thee [O Muhammad] as Our Apostle amidst a community [of unbelievers] before whose time [similar] communities have come and gone, so that thou might propound to them what We have revealed unto thee: for [in their ignorance] they deny the Most Gracious! Say: "He is my Sustainer. There is no deity save Him. In Him have I placed my trust, and unto Him is my recourse!" 30 And even if there were a Quran with which the mountains were made to pass away, or the earth were travelled over with it, or the dead were made to speak thereby; nay! the commandment is wholly Allah's, Have not yet those who believe known that if Allah please He would certainly guide all the people? And (as for) those who disbelieve, there will not cease to afflict them because of what they do a repelling calamity, or it will alight close by their abodes, until the promise of Allah comes about; surely Allah will not fail in (His) promise. 31