Say (O Muhammad SAW): "O mankind! I am (sent) to you only as a plain warner." 49 And [know that] those who attain to faith and do righteous deeds shall be granted forgiveness of sins and a most excellent sustenance; 50 While those who strive to thwart Our revelations, such are rightful owners of the Fire. 51 And We did not send before you any apostle or prophet, but when he desired, the Shaitan made a suggestion respecting his desire; but Allah annuls that which the Shaitan casts, then does Allah establish His communications, and Allah is Knowing, Wise, 52 [And He allows doubts to arise] so that He might cause whatever aspersion Satan may cast [against His prophets] to become a trial for all in whose hearts is disease and all whose hearts are hardened: for, verily, all who are [thus] sinning [against themselves] are most deeply in the wrong. 53 (He also does this) in order that those endowed with knowledge may know that it is the Truth from your Lord and that they may have faith in it and their hearts may humble themselves before Him. Verily Allah always directs those that believe to the Right Way. 54 And the disbelievers will always be in doubt of it, to the extent that the Last Day will suddenly come upon them, or will come upon them the punishment of a day the result of which is not at all good for them. 55 On that Day all sovereignty shall be Allah's and He will judge among them. Then those who believed and acted righteously shall be in Gardens of Bliss. 56 But those who did not believe and called Our revelations lies, will be given disgraceful punishment. 57