Tafsir of Ghafir 40:20

والله يقضي بالحق

And Allah judges with truth, means, He judges with justice. Al-A`mash narrated from Sa`id bin Jubayr from Ibn Abbas, may Allah be pleased with him, that this Ayah means: "He is able to reward those who do good with good and those who do evil with evil.''

إن الله هو السميع البصير

Certainly, Allah! He is the All-Hearer, the All-Seer. This is how it was interpreted by Ibn Abbas, may Allah be pleased with him. This is like the Ayah:

ليجزى الذين أساءوا بما عملوا ويجزى الذين أحسنوا بالحسنى

that He may requite those who do evil with that which they have done, and reward those who do good, with what is best. (53:31)

والذين يدعون من دونه ﻻ يقضون بشيء

while those to whom they invoke besides Him, cannot judge anything

والذين يدعون من دونه

(while those to whom they invoke besides Him), means, the idols and false gods,

ﻻ يقضون بشيء

(cannot judge anything). means, they do not possess anything and they cannot judge anything.

إن الله هو السميع البصير

Certainly, Allah! He is the All-Hearer, the All-Seer. means, He hears all that His creatures say and He knows all about them, so He guides whomsoever He wills and sends astray whomsoever He wills. And He judges with perfect justice in all of that