Charles Ellicott Commentary Job 37:15

"Dost thou know how God layeth [his charge] upon them, And causeth the lightning of his cloud to shine?" — Job 37:15 (ASV)

Light of His cloud — i.e., lightning, as before. “Do you know all the secrets of God’s thunderbolts, at whom and how He will use them?” Some understand this otherwise: “Do you know when God sets the sun over them (the clouds), and causes the light (i.e., the sun) to shine upon His cloud?” i.e., “Do you know how God uses the sun to disperse the clouds?”