Romans 11:22, Note, then, the kindness and severity of God: severity toward those who have fallen, but God’s kindness to you, provided you continue in His kindness. Otherwise you, too, will be cut off.
This is a hard word. The theologian of glory will want to ignore God’s severity and over-emphasise His kindness. God is kind, yes, but He is also holy, thus His holiness can be severe for some. What is God’s kindness? That He grafts Gentiles into Christ the vine (vv. 11-24)—indeed, that He even bothered to save mankind in the first place.
Jesus came to the Jews first—His people—but He also made room for the Gentiles. This was no afterthought; this was always God’s plan (cf. Isaiah 56:6-8; Hosea 1:10; 2:23; Acts 15:7-9; 28:28; John 10:16). It is God’s kindness that you, a Gentile, fear, love, and trust Him. It is God’s kindness that He has given you salvation, which you do not deserve and can never earn.
Any who do not fear, love, and trust God—or fall from His grace—face His severity. This reality makes us uncomfortable, Christian and non-Christian alike. The theologian of glory within us wants to defend God’s severity—even me—but God does not need our defence. God is God; you are not. God is holy, and His holiness becomes severe against those who are not grafted in Christ the vine; there is no other way to deal with sin and evil than with fire, just as one does with fallen branches (John 15:6).
If this frightens you, you have the fear of God, which is the beginning of wisdom (Proverbs 9:10). Wisdom turns to God in fear, and He provides comfort with His Word through the Gospel in Jesus Christ our Saviour. In Christ, you have nothing to fear; when you do fear, He brings that fear to an end.