Romans 2:5 NASB
“But because of your stubbornness and unrepentant heart you are storing up wrath for yourself in the day of wrath and revelation of the righteous judgement of God,”
God has offered His kindness and mercy to those who would repent. But Paul, in an urgency to wake his readers from spiritual lethargy, charges them with “stubbornness and an unrepentant heart”. Stubbornness is better translated as hardened, in the greek the word is “sklerotes” which denotes a callousness and hardness. So what the readers have done is built a callousness around their hearts. Instead of being humble and receptive of the words of Jesus they’ve become hard and resistant to the truth. What a dangerous place to be in, to know the one true God and believe in Him, but to have hardened your heart and be unrepentant in your heart and mind. The readers are faced with the truth that they have stored up the wrath of God for the great day of judgement. This reference Paul makes is the same that the Old Testament Prophets made towards “the day of wrath”. This isn’t in reference to punishment or disciple on earth but in the final day that God judges the whole earth. Mal. 3:2, Amos 5:18, Joel 1:15
This wrath is being stored up for those who are in rebellion towards God, and all of this wrath will be revealed in the righteous judgement of God. When we all stand before God, none will have excuse or an argument to God. All will either be condemned righteously under God’s judgement or be found innocent under the covering of the blood of Jesus.
“‘We must all appear at the judgement seat of Christ, and we must each give an account of himself.’ Therefore, let us serve Him in fear and with all reverence.” Polycarp (c. 135, E), 1.34.
Paul’s focus on the wrath and judgement of God isn’t to scare his readers into religion and being better people. He’s trying to help them understand that there is a critical problem in the heart of mankind and it’s going to bring about complete destruction and judgement for those who continue in rebellion towards God. Paul was a fire and brimstone preacher of his own kind. He understood this better then most of what God’s judgement entails. His rich history in the Torah and all the Hebrew Scriptural books made him completely aware that it’s our sin and rebellion that brings God’s wrath upon us and it’s God’s mercy and grace coupled with our humility and repentance that beings about restoration and right standing with God. It would do us well to be well versed in the Old Testament prophesies of God’s coming judgement to help teach us to love and obey God.