Exodus 4:21

I will harden his heart] God proposes to harden Pharaoh's heart, in order to have the opportunity of displaying His power in the deliverance of His people, and exhibiting His character to the Egyptians. Some take the expression as due to the Eastern and fatalistic way of regarding all that happens in the world as the result of the direct intervention of God. On this interpretation it is simply synonymous with 'Pharaoh's heart was hardened' (Exodus 7:22), and 'Pharaoh hardened his heart' (Exodus 8:15). Where we speak vaguely of the operation of moral and physical laws and of secondary causes, the Oriental frankly says that 'God did this.' He says 'kismet': 'it was fated to be': see on Exodus 4:24. We prefer to say that the hardening of Pharaoh's heart was due to his own obstinacy in refusing to yield to the warnings he received; the Eastern moralist means the same when he says that God hardened his heart. The inevitable result is regarded as the divine purpose. It happens in accordance with laws which God Himself has ordained. 'He will not 'leads inevitably to 'he cannot': cp. Romans 1:28. It should be observed that this, however, is not equivalent to a denial of moral responsibility. It is a man's own fault if he allow himself to be entangled in this chain of inevitable consequences. He is, therefore, responsible for the ultimate hardening of his heart through repeated acts of wilful transgression: see on Exodus 10:3.