“For I have hardened his heart in the heart of his servants.” (Shemot 10, 1.)
Many commentators ask, “How is it that Hashem hardened the heart of Pharaoh and took away his free choice so that he would not want to release the Jews from his land even after being stricken with plagues?”
There was once a Jew who lived in an anti-Semitic country. He had a dispute with the Gentile resident of that nation and the case was to come before the local court. The man sent a beautiful gift, secretly to the non-Jewish judge. Upon receipt, the judge asked him “How is it that you are sending me a bribe? Doesn’t it say in your holy Torah that it is forbidden to bribe the judge, because his heart and mind will be prejudiced in favor of the one who sent the gift? Don’t your rabbis teach that bribes blind judges and prevent a just judgment from taking place?”
The Jew replied calmly. “If two Jews came before you in dispute I know that your mind in regard to them would be fair and just. You would see them as equals. You would not have any prejudices and because of that, you might be able to reach a true and fair judgment. Therefore, if one would give you a bribe, he is ruining the possibility of you doing your job properly and according to the truth because he would tilt the scales of judgment in his favor. This is not the case in my trial, because in my dispute one of the claimants is of your people, and I am a simple Jew. I only sent you the bribe so that you would lean towards me and make it even again in your eyes and give you the chance to rule in this case in a fair and just manner.”
Now, perhaps we can understand hardening of Pharaoh’s heart. The Pharaoh did not wish to release the Jews from bondage. When Hashem struck him heavily with plagues, there was a strong possibility that he would give in and release the Jews even though that was not his true desire. In other words, the plagues would have removed his free will from him. Therefore Hashem, hardened his heart to balance his true wish to afflict the Jews against the power of the plagues. With the power of the plagues on one side and the hardening of his heart on the other the balance scale was now even. This gave Pharaoh a chance to make his choice as to what he wished to do. The true will of Hashem, is that everyone should have free choice in order to earn reward for good deeds and punishment for bad. In the end, the power of the 10th plague made Pharaoh get up in the middle of the night -seek Moshe and Aharon – and of his own free will chase the Jews out of his land.