How does belief in Al Quddoos help in strengthening our eman?

The effect of belief in Allah’s name Al-Quddoos is that Allah’s purity also affirms the truth of all that He informs His creatures as Allah said in Surah an-Nisa verse 87:

“Whose speech is more truthful than Allah’s?”

Thus it should serve to remove any doubts that the believer might have in his mind and in anything which Allah promises even if what He has promised is beyond his or her comprehension. For example, Allah promises in Surah ar-Rahman:

“Can the reward for good be other than good?”

One may receive an evil consequence for a good deed and be discouraged from doing further good. So one questions where is the good for the good? The fact that we cannot see good doesn’t mean it isn’t there. Our belief in Allah as being the pure and the holy should give us the confidence in what He has told us. He has promised that the reward for good is good. So even if what we see in front of us appears to be evil, know that there’s good behind it.