God Is Not Ignorant.
For the eyes of the Lord run to and fro throughout the whole earth, to show Himself strong on behalf of those whose heart is loyal to Him. In this you have done foolishly; therefore from now on you shall have wars.” 2 Chronicles 16:9 NKJV
That he acted against his knowledge of God and his providence, Asa could not be ignorant that the eyes of the Lord run to and fro through the earth, strongly to hold with those (so it may be read) whose heart is perfect towards him; that is, That God governs the world in infinite wisdom, and the creatures, and all their actions, are continually under his eye. The eye of Providence is quick-sighted-it runs; it is intent-it runs to and fro; it reaches far-through the whole earth, no corner of which is from under it, not the most dark or distant; and his eye directs his hand, and the arm of his power; for he shows himself strong. Does Satan walk to and fro in the earth? Providence runs to and fro, is never out of the way, never to seek, never at a loss. That God governs the world for the good of his people, does all in pursuance of the counsels of his love concerning their salvation, all for Jacob his servant's sake, and Israel his elect, Isaiah 45:4. Christ is head over all things to his church, Ephesians 1:22.
That those whose hearts are upright with him may be sure of his protection and have all the reason in the world to depend upon it. He is able to protect them in the way of their duty (for wisdom and might are his), and he actually intends their protection. A practical disbelief of this is at the bottom of all our departures from God and double-dealing with him. Asa could not trust God and therefore made court to Benhadad.
That he acted against his interest. He had lost an opportunity of checking the growing greatness of the king of Syria: His host has escaped out of thy hand, which otherwise would have joined with Baasha's and fallen with it.
He had incurred God's displeasure and henceforth must expect no peace, but the constant alarms of war. Those that cannot find in their hearts to trust God forfeit his protection and throw themselves out of it.