'Change' in the Bible

Then he said, "I tell all of you with certainty, unless you change and become like little children, you will never get into the kingdom from heaven.

Jesus told them, "I tell all of you with certainty, tax collectors and prostitutes will get into God's kingdom ahead of you! John came to you living a righteous life, and you didn't believe him, but the tax collectors and prostitutes did. But even when you saw that, you didn't change your minds at last and believe him."