Tafsir of Al-Anbiya' 21:23

He cannot be questioned about what He does, while they will be questioned. He is the Ruler Whose rule cannot be overturned and none can object to it, because of His might, majesty, pride, knowledge, wisdom, justice and subtlety.

وهم يسٲلون

while they will be questioned. means, He is the One Who will ask His creation about what they did. This is like the Ayah:

فوربك لنسلنهم أجمعين

عما كانوا يعملون

So, by your Lord, We shall certainly call all of them to account. For all that they used to do. (15:92-93)

وهو يجير وﻻ يجار عليه

And He protects (all), while against Whom there is no protector. (23:88)