Charles Ellicott Commentary Job 38:36

"Who hath put wisdom in the inward parts? Or who hath given understanding to the mind?" — Job 38:36 (ASV)

Wisdom in the inward parts. —The mention of the inward parts and the heart here, in the midst of natural phenomena, perplexes everyone; but it is a natural solution to refer them to the lightnings personified: “Who hath put such understanding in their inward parts?”