God gave these instructions to the Israelites only. no outsiders was allowed to participate in any of the sacrifices. they could be a part of the camp, but non-participants. The gospel of Jesus Christ was hidden from the Israelites purposely by God to make them jealous that the gentiles knew of their God and worshiped him. the gospel was first to be preached to the tribe of judah known as the Jews, because that tribe was from the tribe of David. then the Israelites. The only one that preached to the gentiles was Paul as instructed by Jesus.,and latter to the jews and israel.