When God's anger couldn't be appeased

God easily forgives when the heart is truly repentant.

But in the Old Testament times, there was an instance where God was already hurting for a long time that He just couldn't forgive the sins of King Manasseh and the people of Judah. Although the next king who succeeded him, King Josiah, made earnest efforts to undo the evil practices of his predecessor, still God's anger against Judah just couldn't be quenched. 

In 2 Kings 23:25-27, it says, "Neither before nor after Josiah was there a king like him who turned to the Lord as he did - with all his heart and with all his soul and with all his strength, in accordance with all the law of Moses. Nevertheless  the Lord did not turn away from the heat of his fierce anger, which burned against Judah because of all that Manasseh had done to arouse his anger. So the Lord said, 'I will remove Judah also from my presence as I removed Israel, and I will reject Jerusalem, the city I chose, and this temple, about which I said, ‘My Name shall be there.’" (Boldface added for emphasis.)

Yes, God can certainly forgive us when we sin. But we can also expect that we will suffer the "wrath" of the consequences of our acts.