Johan correctly pointed out I appeared to contradict myself. Apologies. Sorry about that.

The phrase "bend wills" was originally used to imply the idea that God forces people to do things against their will, which would absolve them of responsibility. I meant to say that God never does this.

But He is on record as hardening some hearts and softening others. He does this without removing responsibility for actions. He also controls everything through providence. These two actions I referred to with the word "manipulate". Definitely a poor word to use.

Hardening some hearts and softening others may seem unfair, yet scripture declares it outright:

rom 9:21 Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour?
rom 9:22 What if God, willing to show his wrath, and to make his power known, endured with much longsuffering the vessels of wrath fitted to destruction:
rom 9:23 And that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory,

God's providential rulership gives Him absolute control over everything and yet preserves our responsibility in all we do. God hardened Pharoh's heart, yet Pharoh will be held guilty for his actions. God is not the author of sin, and yet He can and does use sinful people and their actions for His purposes.

I suspect that you would be far better off reading the reformers on this subject. Edwards, Calvin, and Luther did devoted much effort to developing the doctrine. Since it is a deep subject it is worth taking the time to read something that develops the doctrine thoroughly.