3 Then I went down to the potter's house, and there he was, making something at the wheel.
4 And the vessel that he made of clay was marred in the hand of the potter; so he made it again into another vessel, as it seemed good to the potter to make.
5 Then the word of the LORD came to me, saying: 6 "O house of Israel, can I not do with you as this potter?" says the LORD. "Look, as the clay is in the potter's hand, so are you in My hand, O house of Israel!Jeremiah 18:3-6

There isn't anybody that can't be changed by the masterful hands of the Lord. There are many though, who will not be changed by Him. It's a matter of choice. Free will. It's up to each and every person on the planet to decide whether God is true, whether He exists or not, and if He does, whether or not to turn aside from an allegiance to the world and turn to Him.

Do you ever think about that? About the choice we have. I mean, what if you walk into a church and you hear a message that speaks to you, to your heart about God and about your life and you are really moved and choosing God makes sense to you, but for one reason or another you leave and do nothing about it? When that happens you've made a choice.

When somebody talks with you on a one to one basis about Jesus and shows you the truth of His life and Word, but you worry about whether or not your family or friends might accept what you've heard, so you do nothing about it, you've made a choice.

So do we have the ability to foil God's will? Mess up His plan? Not really. It was man's choice in the first place to fall away from God. It's God in His mercy, by His grace, Who sent His Son to us and Who gave us the right to choose to come back to Him and to become part of His family.

It's His plan to give us a choice. His are the potter's hands, and when we turn to Him, and surrender ourselves to Him like the lumps of clay that we are, He starts with something unshaped and meaningless and shapes us into a vessel that can be used to display His glory.