Roma 11:13-16

11:13 Now I am speaking to you Gentiles. Seeing that I am an apostle to the Gentiles, I magnify my ministry, 11:14 if somehow I could provoke my people to jealousy and save some of them. 11:15 For if their rejection is the reconciliation of the world, what will their acceptance be but life from the dead? 11:16 If the first portion ¹  of the dough offered is holy, then the whole batch is holy, and if the root is holy, so too are the branches. ² 

Roma 11:29

11:29 For the gifts and the call of God are irrevocable.

[11:16]  ¹ tn Grk “firstfruits,” a term for the first part of something that has been set aside and offered to God before the remainder can be used.

[11:16]  ² sn Most interpreters see Paul as making use of a long-standing metaphor of the olive tree (the root…the branches) as a symbol for Israel. See, in this regard, Jer 11:16, 19. A. T. Hanson, Studies in Paul’s Technique and Theology, 121-24, cites rabbinic use of the figure of the olive tree, and goes so far as to argue that Rom 11:17-24 is a midrash on Jer 11:16-19.