Paul is comparing his death with the Old Testament ritual where wine or olive oil is poured on top of or beside the animal sacrifice that a worshiper would offer to God. What Paul means is that he would gladly die for the Philippians if that would make them more pleasing to God. Also, "is poured out" is passive. It can be translated as an active clause: "But, even if the Romans decide to execute me, I will greatly rejoice if my death will make your faith and obedience more pleasing to God." (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-activepassive]])