Job 36:5 (ESV)

5 “Behold, God is mighty, and does not despise any; he is mighty in strength of understanding.

God is not only mighty, but also mighty in strength of understanding (which is the literal translation of the phrase firm in his purpose). This means that he never uses his might in a random or cruel way. He acts from his heart; in other words, he acts with love, purpose, and understanding. Clearly, Job desperately needs to be reminded of this. He has begun to lose faith in God’s heart, defending his own righteousness at the cost of God’s righteousness (Job 32:2).