A word of warning

^17-21 But if some of the branches of the tree have been broken off, while you, like shoots of wild-olive, have been grafted in, and don’t share like a natural branch the rich nourishment of the root, don’t let yourself feel superior to those former branches. (If you feel inclined that way, remind yourself that you do not support the root, the root supports you.) You may make the natural retort, “But the branches were broken off to make room for my grafting!” It wasn’t quite like that. They lost their position because they failed to believe; you only maintain yours because you do believe. The situation does not call for conceit but for a certain wholesome fear. If God removed the natural branches for a good reason, take care that you don’t give him the same reason for removing you.

^22-24 You must try to appreciate both the kindness and the strict justice of God. Those who fell experienced his justice, while you are experiencing his kindness, and will continue to do so as long as you do not abuse that kindness. Otherwise you too will be cut off from the tree. And as for the fallen branches, unless they are obstinate in their unbelief, they will be grafted in again. Such a restoration is by no means beyond the power of God. And, in any case, if you who were, so to speak, cuttings from a wild-olive, were grafted in, is it not a far simpler matter for the natural branches to be grafted back onto the parent stem?

God still has a plan for Israel

^25-27 Now I don’t want you, my brothers, to start imagining things, and I must therefore share with you my knowledge of God’s secret plan. It is this, that the partial insensibility which has come to Israel is only to last until the full number of the Gentiles has been called in. Once this has happened, all Israel will be saved, as the scripture says: ‘The deliverer will come out of Zion, and he will turn away ungodliness from Jacob, for this is my covenant with them, when I take away their sins’.