New Revised Standard Version
But you and your sons with you shall diligently perform your priestly duties in all that concerns the altar and the area behind the curtain. I give your priesthood as a gift; any outsider who approaches shall be put to death.

Contemporary English Version
But only you and your sons can serve as priests at the altar and in the most holy place. Your work as priests is a gift from me, and anyone else who tries to do that work must be put to death.

New American Bible
But you and your sons with you must take care to exercise your priesthood in whatever concerns the altar and the area within the veil. I give you your priesthood as a gift. Any unauthorized person who comes near shall be put to death.

Douay-Rheims Bible
But thou and thy sons look ye to the priesthood: and all things that pertain to the service of the altar, and that are within the veil, shall be executed by the priests. If any stranger shall approach, he shall be slain.

But thou and thy sons look ye to the priesthood: and all things that pertain to the service of the altar, and that are within the veil, shall be executed by the priests. If any stranger shall approach, he shall be slain.

Therefore thou.

Numbers 18:5 Watch ye in the charge of the sanctuary, and in the ministry of the altar: lest indignation rise upon the children of Israel.

Numbers 3:10 To Aaron and to his sons, to whom they are delivered by the children of Israel. But thou shalt appoint Aaron and his sons over the service of priesthood. The stranger that approacheth to minister, shall be put to death.

within

Leviticus 16:2,12-14 And he commanded him, saying: Speak to Aaron thy brother, that he enter not at all into the sanctuary, which is within the veil before the propitiatory, with which the ark is covered, lest he die, (for I will appear in a cloud over the oracle), . . .

Hebrews 9:3-6 And after the second veil, the tabernacle which is called the Holy of Holies: . . .

as a service

Numbers 16:5-7 And speaking to Core and all the multitude, he said: In the morning the Lord will make known who belong to him, and the holy he will join to himself: and whom he shall choose, they shall approach to him. . . .

1 Samuel 2:28 And I chose him out of all the tribes of Israel to be my priest, to go up to my altar, and burn incense to me, and to wear the ephod before me: and I gave to thy father's house of all the sacrifices of the children of Israel.

John 3:27 John answered and said: A man cannot receive any thing, unless it be given him from heaven.

Romans 15:15,16 But I have written to you, brethren, more boldly in some sort, as it were putting you in mind, because of the grace which is given me from God, . . .

Ephesians 3:8 To me, the least of all the saints, is given this grace, to preach among the Gentiles the unsearchable riches of Christ:

Hebrews 5:4 Neither doth any man take the honour to himself, but he that is called by God, as Aaron was.

the stranger

Numbers 18:4 But let them be with thee, and watch in the charge of the tabernacle, and in all the ceremonies thereof. A stranger shall not join himself with you.

Numbers 3:38 Before the tabernacle of the covenant, that is to say on the east side shall Moses and Aaron camp, with their sons, having the custody of the sanctuary, in the midst of the children of Israel. What stranger soever cometh unto it, shall be put to death.

Numbers 16:40 That the children of Israel might have for the time to come wherewith they should be admonished, that no stranger or any one that is not of the seed of Aaron should come near to offer incense to the Lord, lest he should suffer as Core suffered, and all his congregation, according as the Lord spoke to Moses.