The situation took a turn for the worse when Zimri brought Cozbi into the camp. Until now, the sinning had taken place in the Moabite and Midianite camps. Evidently Zimri had contempt for the covenant, the tabernacle, Moses, the priests, and God"s judgment on the leaders of Israel including his father ( Numbers 25:14). He took Cozbi into the tabernacle and had intercourse with her there before Moses. They did this according to the custom of Baal worship. We should view Phinehas" Acts , therefore, as divine judgment on this attitude and action, not as murder. He slew them in the act of intercourse by driving his spear through both their bodies (lit. bellies). Thus Phinehas (an Egyptian name meaning "the dark-skinned one"), the son of the high priest, atoned for this sin ( Numbers 25:13). [source][source][source]
"The point was that in joining the sexual frenzies of the sacrificial feasts of Baal, the man and his priestess-partner now act to transform the worship of the Lord into the type of sexual rites that were the mode of Canaan. Had this outrage not been stopped, there could never have been true worship in the Holy Place again. They were making the place of entrance into a bordello, the entrance of the meeting of God and man into a trysting spot. [source][source][source]
"We may observe that while priests were always male in Israel, priests could be women in the pagan religions that surrounded Israel. In fact, the sexually centered religions of Canaan would have catered to women in their priesthood. Women priests were so very closely tied to the sexual outrages of Baal and Asherah worship that the very notion of a women [1] priest conjured up images of sexual worship. Perhaps this is the principal reason that Israel had no women priests." [2][source]
"Amid the time of apostasy, the writer points to ... the need for new forms of leadership.... In this narrative, Moses is remarkably ineffective in the face of a blatant transgression ( Numbers 25:6). The day was saved, however, by the decisive action of one from the next generation of priests, Phinehas, the grandson of Aaron." [3][source]