So Paul went above and beyond. Not only was he just circumcised, a Hebrew of Hebrews (things he could not control), but he was outstanding as an Israelite.
Not just as a Pharisee, but he was a standout one at that. Not just a Pharisee, but the best of the best when it comes to zeal. His was a misguided zeal, but who can blame him? He later said God has mercy on him because he did it in ignorance.
I am grateful to the one who has strengthened me, Christ Jesus our Lord, because he considered me faithful in putting me into ministry, even though I was formerly a blasphemer and a persecutor, and an arrogant man. But I was treated with mercy because I acted ignorantly in unbelief, and our Lord’s grace was abundant, bringing faith and love in Christ Jesus. (1 Timothy 1:12-14)
He is saying God reached out to me. If there was someone that should not be saved, Paul is saying, that should be me.
But back to the focus verse, which introduced the concept of zeal, and the fact that zeal can be misplaced. Paul said elsewhere that Israel has zeal but not according to knowledge (Romans 10:2).
It is like driving very fast but in the wrong direction. You are driving fast, but by the time you arrive, it will be a waste of time, a regrettable experience, and a waste of energy, and you will be worse off than if you had no zeal in the first place.
And so millions of people are driving fast (zeal) but in the wrong direction (not according to knowledge)
Brothers and sisters, my heart’s desire and prayer to God on behalf of my fellow Israelites is for their salvation. For I can testify that they are zealous for God, but their zeal is not in line with the truth. For ignoring the righteousness that comes from God and seeking instead to establish their own righteousness, they did not submit to God’s righteousness. For Christ is the end of the law, with the result that there is righteousness for everyone who believes. (Romans 11:1-4)
No one needs to tell Paul that Israel had zeal, meaning they prioritized doing what would please God —and for good reasons. But the question was righteousness.
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Every other religion is based on ways to attain righteousness, but Christianity is the truth. Every other religion has a cast of priests who are human intermediaries, but in Christianity, it's God who serves as the intermediary between God and man. God became man to fully secure salvation so that there is no loophole for us to drop off, but we are fully secured in the presence of God, where Christ is ever living to intercede for us (Hebrews 7:25).
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So Paul did not indict the zeal of Israel, but their lack of following the truth.
John 14:6: Jesus replied, “I am the way, and the truth, and the life. No one comes to the Father except through me. (John 14:6)
And Paul is not giving a blanket indictment of a group/race. Paul was also an Israelite. He did not deny that part of himself. So while he uses the phrase "my fellow Israelites," he is making a generalization, but there are, of course, exceptions to that rule, which he assumes his readers understand.
Nevertheless, understand that these people were the original people of God. And later, Paul would call gentile believers to humility and to not be disdainful of Jews; that we should realize that everything is in the hands of God, not ours (Romans 11).
And the verse we are focused on is also about zeal and righteousness. Paul, by revelation, showed a new way of righteousness, which is not something you do, but a gift you receive, that you submit to.
So both Israel and Gentiles are called to humility. God would have no boasting before Him (1 Corinthians 1:29); He just would not. Everyone must come believing that they need the grace God gives, grounded in truth —His revelation in Christ —hence the need for preaching as a means through which Christ saves (1 Corinthians 1:21).
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And notice how Paul spoke about the Gentiles versus the Israelites. He called the gentile Philippians his brothers and sisters (there might have been some Jews there also), which shows you he now prioritizes his spiritual heritage above his natural heritage.
That indicates a shift. That same shift was first spoken of by Jesus, who talked about worshippers and about not worshipping in Jerusalem or on a mountain (John 4:21-24), and that spiritual connection now trumps natural connection (Matthew 12:48-50).
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So in Paul's zeal, he persecuted the church. That is such a picture of how religion can lead to violence, and people would justify it. Pau; was that person, and that persecution itself was a way for him to earn righteousness.
He did what God did not like in a bid to please God. That is confusion. But that is the state of all religions apart from Christ Jesus.
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So don't confuse zeal in practitioners of other religions for truth, and don't confuse mere moral uprightness with righteousness.
They may have a wrong definition of sin that excludes thoughts and emotions, contrary to what Jesus said (Matthew 5).
Remember, Paul was blameless regarding the externality of the law, but in his letter to Timothy, he said he was arrogant (1 Timothy 1:13). Many people would not think of arrogance as an issue, but God sees into the heart.
So sin and righteousness, as defined by God, mean our righteousness is like a menstrual rag (Isaiah 64:6), and the only solution is Christ - the gift of righteousness we have in Him (2 Corinthians 5:21).
From Addiction to Freedom by Favour Oyinloye