Who is the Stranger?

In Numbers 1 when God tells Moses to number the people, He tells Moses not to count the Levites. The Levites will be in charge over the tabernacle. at the end off verse 51 it says that the stranger that comes near to the tabernacle will be put to death. It sounds like the stranger is anyone that is not a Levite. Yet in Lev. 4 God commands that one [common folk and rulers(non-Levites), in addition to priest] bring their sin offering to the brazen alter (that was the first piece of furniture inside the tabernacle) and make their sacrifice. So, a non-Levite with a sin offering is not a stranger or he would have been put to death. I'm a little confused. Who is the 'stranger' in Numbers 1:51?

Num 1:50 But thou, appoint the Levites over the tabernacle of testimony, and over all the vessels thereof, and over all things that belong to it: they shall bear the tabernacle, and all its vessels; and they shall serve it, and round about the tabernacle shall they encamp;
Num 1:51 and when the tabernacle setteth forward, the Levites shall take it down; and when the tabernacle encampeth, the Levites shall set it up; and the stranger that cometh near shall be put to death.

Lev. 4 22 'When a ruler has sinned, and done something unintentionally against any of the commandments of the Lord his God in anything which should not be done, and is guilty, 23 or if his sin which he has committed comes to his knowledge, he shall bring as his offering a kid of the goats, a male without blemish. 24 And he shall lay his hand on the head of the goat, and kill it at the place where they kill the burnt offering before the Lord. It is a sin offering.

27 'If anyone of the common people sins unintentionally by doing something against any of the commandments of the Lord in anything which ought not to be done, and is guilty, 28 or if his sin which he has committed comes to his knowledge, then he shall bring as his offering a kid of the goats, a female without blemish, for his sin which he has committed. 29 And he shall lay his hand on the head of the sin offering, and kill the sin offering at the place of the burnt offering.

 

I like the bit in Hebrews that says Jesus becomes our high priest.

But Christ being come high priest of the good things to come, by the better and more perfect tabernacle not made with hand, (that is, not of this creation,) nor by blood of goats and calves, but by his own blood, has entered in once for all into the [holy of] holies, having found an eternal redemption. For if the blood of goats and bulls, and a heifer's ashes sprinkling the defiled, sanctifies for the purity of the flesh, how much rather shall the blood of the Christ, who by the eternal Spirit offered himself spotless to God, purify your conscience from dead works to worship [the] living God? Heb 9:11-13

Back to the 'stranger': If any non-Levite is condemed to death for coming near the tabernacle, then how could rulers or common people make their sin offerings (which they are commanded to do)? I have two thoughts

1. sometimes the word 'tabernacle' was used in refence to the sanctuary and holy of holies (not the court - where the altar of sacrifice was). Maybe this is how it is used in Numbers 1.

2. maybe it means an unauthorized person. the only authorized persons would be the Levites and Priests and unintentional sinners, whose sin has come to his knowledge.

 

If the prohibition was only during the "setting up" of the Tabernacle (I did not read it this way at first), then what you say may make sense. Could it be the ark that the people were not permitted to see? The ark of the testimony had to be covered by the vail each time it was moved.

Exd 40:3 And thou shalt put therein the ark of the testimony, and cover the ark with the vail.
Exd 40:21 And he brought the ark into the tabernacle, and set up the vail of the covering, and covered the ark of the testimony; as the LORD commanded Moses.
Num 4:5 And when the camp setteth forward, Aaron shall come, and his sons, and they shall take down the covering vail, and cover the ark of testimony with it:

'Approach' was everything. Under the Law, one could only approach God through the high priest, in the Holy of Holies, once a year, not without (animal's) blood. This is explained as a type in Hebrews, Jesus is our better high priest. And '... by his own blood, has entered in once for all into the [holy of] holies, having found an eternal redemption.'