Paul abruptly shifts his tone in this third chapter of Philippians. The reason why isn’t clear, but his message is very much so.
You can see this passage in Philippians 3:2-4a:

Paul’s change in tone is very abrupt here, but not completely unusual for Paul. However, this is more abrupt than any other occurrence. The reason for his change in tone is unclear. Perhaps he was made aware of this as a new problem as he was dictating this letter.
Up until this point in his letter to the Philippians, Paul has dealt with internal problems the church in Philippi was facing. This one seems to be a threat from the outside. It is clear that this threat is Jewish in its origination, and Paul deals with it with certainty.
In this brief passage, Paul uses three very descriptive negative terms about those who are threatening the church, and then four positive descriptors of the believers.

