Paul develops an accounting metaphor in Philippians 3:7. All of his achievements listed in the previous verses count for nothing when it comes to his position in Jesus Christ. On one side of the ledger is his human achievement, on the other is the sake of Christ. He writes them off as a loss in comparison to knowing Christ Jesus as his Lord.
Human achievement is “loss” or “rubbish.” Loss (ζημία) can refer to a financial loss, as in Acts 27:10 (Paul predicts the shipwreck and “much injury and loss”). In the Septuagint, 2 Kings 23:33 used the word to refer a heavy tribute imposed on Judah by Pharaoh Neco when he took Jehoahaz captive. The word can refer to a financial penalty (a heavy fine, for example). In this context, Paul is saying that all of human achievement was a huge loss when it came to knowing Jesus and the power of the resurrection.
Imagine someone who buys an antique at an estate sale, investing a significant amount of money because they were certain it was worth far more (maybe a Civil War Rifle or a colonial document). They take the antique to the Antiques Roadshow and have it examined by an expert and it turns out to be a worthless fake. The person would take a huge loss since they cannot resale the item and recoup their investment. It is still a nice antique and might look nice good hanging over the mantel. It can still be enjoyed and valued. But it is really a total financial loss.
In a similar way, Paul’s “heavy investment” in training as a Pharisee and his dedicated practice of Judaism as a Pharisee have turned out to be a loss if the return on the investment was “righteousness before God.” He still has the value of a thorough knowledge of the Scripture and the satisfaction of a life well lived, good moral values and work ethic, etc. But with respect to being right with God, that investment is a total loss.
The second word Paul uses here is more picturesque. Rubbish (σκύβαλον) refers to refuse or garbage, the sort of thing the dogs would scavenge. Often refers to excrement (Josephus, JW 5.571, “sewers and cattle dung”; Sib.Or. 7.58, “the mournful refuse of war”). The word appears in the medical work of Aretæus the Cappadocian, Causes and Symptoms of Acute Disease (SD 2.9), in a section entitled “On Dysentery.” The third edition of Bauer’s Lexicon (BDAG) glosses the word in this context as “It’s all crap.” It is no coincidence Paul is more or less saying the opponents as “dogs” who they are still rooting around in their own skubalon!
It is important to understand Paul correctly here: Paul is not saying Judaism is bad, or that Jews keeping the Law is bad, or that Torah is “garbage.” He is saying that keeping the Law does not make one right with God, only faith in Jesus Christ will do that. In Galatians he will address the reasons why a Gentile is not under the Law, but here his point is only that human achievement (whether good or bad) counts for nothing with respect to being right with God, knowing the “power of the resurrection” or obtaining salvation at the resurrection of the dead.
The righteousness that counts is the righteousness that comes “through faith of Christ” (v.9). There is a serious interpretive issue here in verse nine. The ESV and the NIV both translate the line as “through faith in Christ Jesus” although “in” is not the natural way to read the text. “through the faith of Christ” is a better rendering of the Greek, but what does this mean? (Yes, this is the classic pistis christou debate!)
There are two options here. Paul might mean “the faith that I have in Jesus’ sacrifice saves me from sin.” On the other hand, “the faithful act of Jesus’ sacrifice on the cross saves me from my sin (through the faithful obedience of Christ on the cross).” Since both of these options are taught in Scripture (you do place your faith in Jesus, Eph 2:8-9) and Jesus was faithful when he humbly submitted to death of the cross (Phil 2:5-11), it is possible most people do not catch Paul’s subtle teaching here. In the context of Philippians, Jesus is the one who humbly submitted himself to the Father and was obedient to death, Paul has submitted to the Father and suffers in prison at the moment; Epaphroditus humble serves the church at Philippi at the very moment even though he has suffered.
It is difficult to have Paul’s attitude toward personal achievement. In the Roman world, one would naturally boast of their achievements and claim honors for themselves. In contemporary American culture, humility is a virtue, but we still like to boast about our achievements. University professors put their PhD up on their office walls, athletes have personal trophy cases, pastors humble-brag about attendance in their church. How would our ersonal lives be transformed if we really had the attitude of Christ Jesus and set aside our honor in order to serve others? Do we really need to consider all our achievement to be “crap”?