Romans 11:22-24

22Notice how God is both kind and severe. He is severe toward those who disobeyed, but kind to you if you continue to trust in his kindness. But if you stop trusting, you also will be cut off.

23And if the people of Israel turn from their unbelief, they will be grafted in again, for God has the power to graft them back into the tree.

24You, by nature, were a branch cut from a wild olive tree. So if God was willing to do something contrary to nature by grafting you into his cultivated tree, he will be far more eager to graft the original branches back into the tree where they belong.