What is everything God does on our behalf based on?
Everything God has done and continues to do on humanity's behalf rests on the finished work of the cross, where He did not spare His Son. That sacrifice was necessary so God could purchase mankind back to Himself, while remaining consistent with His holy, righteous principles. He never acts contrary to His own character.
Les explains that this truth is anchored in Romans chapter 8, still in verse 32. He emphasizes that everything God now has done and is doing on our behalf is based upon the finished work of the cross, where God did not spare His Son. The purpose was so that He could purchase mankind back to Himself. Les also notes that God is sovereign and could do things any way He wanted, but He never goes against His own principles. God is holy, righteous, omnipotent, and full of all knowledge, so He knows what has to be done to reconcile fallen man back to Himself.
He that spared not his own Son, but delivered him up for us all, how shall he not with him also freely give us all things?