The apostle Paul comments on the hypocrisy that often occurs when judging others. This is a clear explanation of Jesus' illustration of a man with a plank in his eye critically pointing out the speck in someone else's (Matthew 7:3-5)!
In the original Greek, "inexcusable" in Romans 2:1 is literally "defenseless." In the spiritual court of law, there is no defense for the actions of a person who commits the same sin of which he accuses another. An interesting aspect of this appears when we understand a more thorough meaning of the word "practice" (prassoo) that occurs later in the verse. It means to perform repeatedly or habitually, to do exactly. We can infer from this that Paul means these accusers have not only committed the particular sin before but are also continuing to commit it!
We cannot properly assess what a righteous standard is if we use others or ourselves—fallible human beings—as the standard. True judgment is according to the truth of God. Paul makes this very point in the next verse: "But we know that the judgment of God is according to truth against those who practice such things" (Romans 2:2).
God's righteous judgment is based on truth. This means that His decisions are reached based on reality, on the facts of the case, not on appearances or intentions. It also means He judges without partiality to rank, wealth, station, or position. Finally, it means that He judges against an authoritative and unchanging standard: His own character as revealed in His Word.
Judging our lives according to how others live is a sure way to neglect and ignore serious problems in our own lives. Continuing in verse 3, Paul writes, "And do you think this, O man, you who judge those practicing such things, and doing the same, that you will escape the judgment of God?" God pronounces judgment on those who make a practice of indulging in sin. The apostle makes it quite certain that all sin will be judged. No one will "get away with it."
Some, indulging in self-praise, write their own testimonials to promote themselves because they are full of impatient pride, unable to wait for the acknowledgment and praise of others for their accomplishments. In their own foolishness, these people try to establish their own conduct as the norm and then find great satisfaction in always measuring up to the standard that they have set.