The former preach Christ out of selfish ambition, not sincerely, supposing that they can stir up trouble for me while I am in chains. Philippians 1:17, NIV

Why did Paul keep on rejoicing even though some were proclaiming Christ from unrighteous cause?

Paul’s commission as an apostle would be achieved. Prayers of the saints in Philippi and the holy spirit would all turn out good for the Kingdom of God. Paul would be protected and stand in front of Jesus’s glory. Paul’s goal was to magnify Jesus Christ. Paul was determined to live and die for Christ, sharing in Christs sufferings and His resurrection. Paul’s sincere expected and hoped that he wouldn’t be put to shame in any way. That he would be able to continue boldly magnifying Jesus in his physical body.