Not having my own righteousness, which is from the law, but that which is through faith in Christ.
To know Jesus Christ is to have His righteousness, His holiness, and His virtue imputed to us, which makes us right before God.
Throughout his earlier life, the apostle Paul tried to attain salvation through strict adherence to the Law. But when he was confronted by the wondrous reality of Christ, he was ready to trade in all his self–righteous and external morals, good works, and religious rituals for the righteousness granted to him through faith in Christ. Paul was willing to lose the thin and fading robe of his reputation if he could only gain the splendid and incorruptible robe of the righteousness of Christ.
This is the greatest of all benefits because it secures our standing before God. It is God’s gift to the sinner, appropriated by faith in the perfect work of Christ, which satisfies God’s justice.
not having a righteousness of my own derived from the Law, but that which is through faith in Christ, the righteousness which comes from God on the basis of faith, (3:9b)
Paul had spent his adult life futilely trying to obtain a righteousness of his own derived from keeping the Law. That righteousness—one of self-effort, external morality, religious ritual, and moral works, all produced by the flesh—had been a crushing, unbearable burden (cf. Matt. 23:4; Luke 11:46; Acts 15:10). Although Paul did his best, he fell far short of God’s standard (cf. Rom. 3:23), which no one can meet: “Now we know that whatever the Law says, it speaks to those who are under the Law, so that every mouth may be closed and all the world may become accountable to God; because by the works of the Law no flesh will be justified in His sight; for through the Law comes the knowledge of sin” (Rom. 3:19–20; cf. Acts 13:39; Gal. 2:16; 3:10–13; 5:4; Eph. 2:8–9). He was like the rest of his countrymen who, “not knowing about God’s righteousness and seeking to establish their own, they did not subject themselves to the righteousness of God” (Rom. 10:3).
In Romans 7:9–13, Paul expands on the awakening in his heart:
I was once alive apart from the Law; but when the commandment came, sin became alive and I died; and this commandment, which was to result in life, proved to result in death for me; for sin, taking an opportunity through the commandment, deceived me and through it killed me. So then, the Law is holy, and the commandment is holy and righteous and good. Therefore did that which is good become a cause of death for me? May it never be! Rather it was sin, in order that it might be shown to be sin by effecting my death through that which is good, so that through the commandment sin would become utterly sinful.
Once, though devoted to the law of Judaism, he was living and thinking apart from the law of God. When he faced the true divine law, he saw himself as a sinner dead in sin and headed for eternal death. The law of Judaism gave him life, he thought. The law of God killed him. When he saw himself as utterly sinful, he renounced works of righteousness of his own doing and accepted the free gift of God’s righteousness by grace.
Paul gladly exchanged the burden of legalistic self-righteousness for the righteousness which is through faith in Christ, the righteousness which comes from God on the basis of faith. Faith is the confident, continuous confession of total dependence on and trust in Jesus Christ for the necessary requirements to enter God’s kingdom. It involves more than mere intellectual assent to the truth of the gospel; saving faith includes trust in the Lord Jesus Christ and surrender to His lordship. It is on the basis of faith alone that righteousness … comes from God to repentant sinners.
Righteousness is right standing with God and acceptance by Him. That repentant sinners have their sin imputed to Christ and His righteousness imputed to them is the heart of the gospel. In 2 Corinthians 5:21, Paul declared that God “made Him [Christ] who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him.” Paul gladly shed the threadbare robe of his own righteousness and stretched out his empty hands to receive the glorious royal robe of God’s righteousness in Christ. This doctrine is at the core of the gospel. On the cross, God judged Jesus as if He had personally committed every sin ever committed by every person who ever truly believed. When a sinner embraces Jesus as Lord and trusts only in His sacrifice for sin, God treats that sinner as if he lived Christ’s sinless life (cf. Isa. 53; 2 Cor. 5:21; 1 Peter 2:24).
3:9 And be found in Him. Here again it sounds as if Paul was still trying to be found in Christ. The fact is that he is looking back to the tremendous decision which faced him before he was saved. Was he willing to abandon his own efforts to earn salvation, and simply trust in Christ? He had made his choice. He had abandoned all else in order to be found in Christ. The moment he believed on the Lord Jesus, he stood in a new position before God. No longer was he seen as a child of sinful Adam, but now he was seen in Christ, enjoying all the favor which the Lord Jesus enjoys before God the Father.
Likewise he had renounced the filthy rags of his own self-righteousness, which he had sought to win by keeping the law, and had chosen the righteousness of God which is bestowed on everyone who receives the Savior. Righteousness is here spoken of as a garment or covering. Man needs righteousness in order to stand before God in favor. But man cannot produce it. And so, in grace, God gives His own righteousness to those who receive His Son as Lord and Savior. “He (God) made Him (Christ) who knew no sin to be sin for us, that we might become the righteousness of God in Him” (2 Cor. 5:21).
Again we would like to emphasize that verses 8 and 9 do not suggest that Paul had not yet received the righteousness of God. On the contrary, this became his possession when he was regenerated on the road to Damascus. But the present tense simply indicates that the results of that important event continued up to the present and that Paul still considered Christ to be worth far more than anything he had given up.
9 Paul mentions his stellar Jewish heritage, privileges, and religious successes but then disavows them, because he now places his hope only in Christ. It is through Christ, and Christ alone, that he hopes to attain the resurrection, which is the fulfillment of the hope of Israel (Ac 23:6; 24:15; 26:6–7; 28:20). As Christ “was found” (heuriskō, GK 2351) in the form of a man (2:7), Paul hopes to be found (same Greek verb) in Christ at the day of the Lord, that he might be acquitted before God in the judgment. His Jewish privileges are found to be worthless in light of the revelation in Christ that the righteousness that counts with God does not derive from one’s heritage or obedience to the law. Paul’s succinct comments about righteousness in these verses show that the nuances of the debate were not at issue in Philippi (cf. deSilva, “No Confidence in the Flesh,” 43). He assumes that the Philippian Christians understand what he means, and we understand better what he means by reading Romans. A right relationship with God is based on being in Christ through faith. Right conduct derives only from serving God by the Spirit. Faith is the admission that one cannot earn God’s approval but can only accept it by grace as a gift.
The problem with righteousness based on the law is that it is a false righteousness founded on human performance, which will ultimately founder because the flesh can be taken over by the power of sin so that even the law—holy, righteous, and good as it is—can be co-opted by sin (Ro 7:5–11). Human righteousness always falls short (Dt 9:4–7), but it can delude one into thinking that one is “faultless” (Php 3:6). Ignorance (Ro 10:2) breeds arrogance and a refusal to submit humbly to God’s righteousness (Ro 10:3).
The phrase “faith in Christ” (lit., “the faith of Christ” [pistis Christou]) continues to spark debate among interpreters (cf. Ro 3:22, 26; Gal 2:16, 20). Some take it as a subjective genitive—“through Christ’s own faithfulness,” referring back to what Christ has done (2:6–11). It is argued that when a genitive follows the word pistis in the LXX, it is almost always a subjective genitive. This grammatical point is buttressed by Paul’s assertion in Romans 5:15 that grace comes through one man’s act of righteousness—Christ’s. Christ’s faithfulness to God secured the promises to Abraham for all who believe. If this view is correct, Paul would be contrasting his righteousness with Christ’s righteousness (cf. Ro 4:3). Being found in Christ makes it possible to share in Christ’s righteousness when one stands before God.
The traditional view interprets “faith of Christ” as an objective genitive, “faith in Christ.” Paul consistently uses the verbal form of faith (pisteuō, GK 4409) to refer to believers’ putting their trust in Christ. Christ is never the subject of a verb that connotes faithfulness, and Paul nowhere says unambiguously that salvation came through Christ’s faithfulness. He unambiguously ties salvation to the believer’s faith in Christ and emphasizes it in 1:29 and 2:17. In this context, the objective genitive seems to be the best option. The second clause, “the righteousness that comes from God and is by faith,” reiterates the first to reinforce the point. Paul contrasts “righteousness of my own,” which is based on his obedience to the law, with the righteousness that belongs to God, which is based on his faith in Christ. This righteousness is bestowed as a free gift. Paul no longer places his confidence in himself and his achievements but in Christ’s achievements for him.
 MacArthur, J. (2001). Truth for today : a daily touch of God’s grace (p. 141). Nashville, Tenn.: J. Countryman.
 MacArthur, J. F., Jr. (2001). Philippians (pp. 237–238). Chicago: Moody Press.
 MacDonald, W. (1995). Believer’s Bible Commentary: Old and New Testaments. (A. Farstad, Ed.) (p. 1973). Nashville: Thomas Nelson.
 Garland, D. E. (2006). Philippians. In T. Longman III (Ed.), The Expositor’s Bible Commentary: Ephesians–Philemon (Revised Edition) (Vol. 12, pp. 241–242). Grand Rapids, MI: Zondervan.