Harm from Allah

You cannot harm Him in the least.

9:39If ye go not forth He will afflict you with a painful doom, and will choose instead of you a folk other than you. Ye cannot harm Him at all. Allah is Able to do all things.

Those who believe in falsehood and deny Allah are the true losers.”

29:52Say (unto them, O Muhammad): Allah sufficeth for witness between me and you. He knoweth whatsoever is in the heavens and the earth. And those who believe in vanity and disbelieve in Allah, they it is who are the losers.

What harm would come to them if they believed in Allah and the Last Day and gave from what He provided them?

4:39What have they (to fear) if they believe in Allah and the Last Day and spend (aright) of that which Allah hath bestowed upon them, when Allah is ever Aware of them (and all they do)?