In these verses, the scriptures say that God hardened Pharoah's heart:
Exodus 4:21 -
21And the LORD said to Moses, "When you go back to Egypt, see that you do before Pharaoh all the miracles that I have put in your power. But I will harden his heart, so that he will not let the people go;
Ex 7:3 - But I will harden Pharaoh's heart, and though I multiply my miraculous signs and wonders in Egypt;
Exodus 9:12 - But the LORD hardened Pharaoh's heart and he would not listen to Moses and Aaron, just as the LORD had said to Moses;
Exodus 10:1 - Then the LORD said to Moses, "Go to Pharaoh, for I have hardened his heart and the hearts of his officials so that I may perform these miraculous signs of mine among them;
Exodus 10:20 - But the LORD hardened Pharaoh's heart, and he would not let the Israelites go;
Exodus 10:27 - But the LORD hardened Pharaoh's heart, and he was not willing to let them go;
Exodus 11:10 - Moses and Aaron performed all these wonders before Pharaoh, but the LORD hardened Pharaoh's heart, and he would not let the Israelites go out of his country;
Exodus 14:4 - And I will harden Pharaoh's heart, and he will pursue them. But I will gain glory for myself through Pharaoh and all his army, and the Egyptians will know that I am the LORD." So the Israelites did this;
Exodus 14:8 - The LORD hardened the heart of Pharaoh king of Egypt, so that he pursued the Israelites, who were marching out boldly; and
Exodus 14:17 - I will harden the hearts of the Egyptians so that they will go in after them. And I will gain glory through Pharaoh and all his army, through his chariots and his horsemen.
These verses indicate that there were also times when Pharoah's heart was clearly hardened of his own accord, and, of course, God knew that from the beginning:
Exodus 7:13 - Yet Pharaoh's heart became hard and he would not listen to them, just as the LORD had said;
Exodus 7:14 - Then the LORD said to Moses, "
Pharaoh's heart is unyielding; he refuses to let the people go;
Exodus 7:22 - But the Egyptian magicians did the same things by their secret arts, and Pharaoh's heart became hard; he would not listen to Moses and Aaron, just as the LORD had said;
Exodus 8:15 - But when Pharaoh saw that there was relief, he hardened his heart and would not listen to Moses and Aaron, just as the LORD had said;
Exodus 8:19 - The magicians said to Pharaoh, "This is the finger of God." But Pharaoh's heart was hard and he would not listen, just as the LORD had said;
Exodus 8:32 - But this time also Pharaoh hardened his heart and would not let the people go;
Exodus 9:7 - Pharaoh sent men to investigate and found that not even one of the animals of the Israelites had died. Yet his heart was unyielding and he would not let the people go;
Exodus 9:34 - When Pharaoh saw that the rain and hail and thunder had stopped,
he sinned again: He and his officials hardened their hearts; Exodus 9:35 - So Pharaoh's heart was hard and he would not let the Israelites go, just as the LORD had said through Moses; and Exodus 13:15 - When Pharaoh stubbornly refused to let us go, the LORD killed every firstborn in Egypt, both man and animal. This is why I sacrifice to the LORD the first male offspring of every womb and redeem each of my firstborn sons.'
These are my findings from my study:
1. I Samuel says: "But the Lord said unto Samuel, Look not on his countenance, or on the height of his stature; because I have refused him: for the Lord seeth not as man seeth; for man looketh on the outward appearance but the Lord looketh on the heart". The condition of Pharoah's heart was no surprise to God.
2. MidniteWelder has already quoted the next scripture I referenced in Romans regarding God's creation of noble and ignoble vessels for His purposes, so I won't repeat it here.
3. Exodus 9:34 answered more questions for me than any. It says that Pharoah
sinned by hardening his heart. Our God is a holy, righteous God who does not force us to sin. HOWEVER, He DOES use evil for good (Romans 8:28 - And we know that in all things God works for the good of those who love Him, who have been called according to His purpose.)
My purpose in posing the question was not contentious in nature.

It was merely a reminder that we need to guard our hearts and constantly question our motives and the things that influence us, either from within or without. For me, this verse is pretty scary:
Exodus 7:14 - Then the LORD said to Moses, "
Pharaoh's heart is unyielding..." How long will God strive with a heart like that???
Psalm 34:18 -
The LORD is close to the brokenhearted and saves those who are crushed in spirit.
James 4:16 - But he gives us more grace. That is why Scripture says: "
God opposes the proud but gives grace to the humble."
Proverbs 4:23 - “Above all else,
guard your heart for it is the wellspring of life.”
No matter what we do or don't do, or how we are influence or not, may we never lose our first love:
Revelation 2
To the Church in Ephesus
1 “To the angel of the church in Ephesus write:
These are the words of him who holds the seven stars in his right hand and walks among the seven golden lampstands.
2 I know your deeds, your hard work and your perseverance. I know that you cannot tolerate wicked people, that you have tested those who claim to be apostles but are not, and have found them false.
3 You have persevered and have endured hardships for my name, and have not grown weary.
4 Yet I hold this against you: You have forsaken the love you had at first. 5 Consider how far you have fallen! Repent and do the things you did at first. If you do not repent, I will come to you and remove your lampstand from its place.
6 But you have this in your favor: You hate the practices of the Nicolaitans, which I also hate.
7 Whoever has ears, let them hear what the Spirit says to the churches. To the one who is victorious, I will give the right to eat from the tree of life, which is in the paradise of God.