These are the generations of Aaron and Moses at the time when the LORD spoke with Moses on Mount Sinai. These are the names of the sons of Aaron: Nadab the firstborn, and Abihu, Eleazar, and Ithamar. These are the names of the sons of Aaron, the anointed priests, whom he ordained to serve as priests. But Nadab and Abihu died before the LORD when they offered unauthorized fire before the LORD in the wilderness of Sinai, and they had no children. So Eleazar and Ithamar served as priests in the lifetime of Aaron their father.
And the LORD spoke to Moses, saying, “Bring the tribe of Levi near, and set them before Aaron the priest, that they may minister to him. They shall keep guard over him and over the whole congregation before the tent of meeting, as they minister at the tabernacle. They shall guard all the furnishings of the tent of meeting, and keep guard over the people of Israel as they minister at the tabernacle. And you shall give the Levites to Aaron and his sons; they are wholly given to him from among the people of Israel. And you shall appoint Aaron and his sons, and they shall guard their priesthood. But if any outsider comes near, he shall be put to death.”
And the LORD spoke to Moses, saying, “Behold, I have taken the Levites from among the people of Israel instead of every firstborn who opens the womb among the people of Israel. The Levites shall be mine, for all the firstborn are mine. On the day that I struck down all the firstborn in the land of Egypt, I consecrated for my own all the firstborn in Israel, both of man and of beast. They shall be mine: I am the LORD.”
And the LORD spoke to Moses in the wilderness of Sinai, saying, “List the sons of Levi, by fathers' houses and by clans; every male from a month old and upward you shall list.” So Moses listed them according to the word of the LORD, as he was commanded. And these were the sons of Levi by their names: Gershon and Kohath and Merari. And these are the names of the sons of Gershon by their clans: Libni and Shimei. And the sons of Kohath by their clans: Amram, Izhar, Hebron, and Uzziel. And the sons of Merari by their clans: Mahli and Mushi. These are the clans of the Levites, by their fathers' houses.
To Gershon belonged the clan of the Libnites and the clan of the Shimeites; these were the clans of the Gershonites. Their listing according to the number of all the males from a month old and upward was 7,500. The clans of the Gershonites were to camp behind the tabernacle on the west, with Eliasaph, the son of Lael as chief of the fathers' house of the Gershonites. And the guard duty of the sons of Gershon in the tent of meeting involved the tabernacle, the tent with its covering, the screen for the entrance of the tent of meeting, the hangings of the court, the screen for the door of the court that is around the tabernacle and the altar, and its cords—all the service connected with these.
To Kohath belonged the clan of the Amramites and the clan of the Izharites and the clan of the Hebronites and the clan of the Uzzielites; these are the clans of the Kohathites. According to the number of all the males, from a month old and upward, there were 8,600, keeping guard over the sanctuary. The clans of the sons of Kohath were to camp on the south side of the tabernacle, with Elizaphan the son of Uzziel as chief of the fathers' house of the clans of the Kohathites. And their guard duty involved the ark, the table, the lampstand, the altars, the vessels of the sanctuary with which the priests minister, and the screen; all the service connected with these. And Eleazar the son of Aaron the priest was to be chief over the chiefs of the Levites, and to have oversight of those who kept guard over the sanctuary.
To Merari belonged the clan of the Mahlites and the clan of the Mushites: these are the clans of Merari. Their listing according to the number of all the males from a month old and upward was 6,200. And the chief of the fathers' house of the clans of Merari was Zuriel the son of Abihail. They were to camp on the north side of the tabernacle. And the appointed guard duty of the sons of Merari involved the frames of the tabernacle, the bars, the pillars, the bases, and all their accessories; all the service connected with these; also the pillars around the court, with their bases and pegs and cords.
Those who were to camp before the tabernacle on the east, before the tent of meeting toward the sunrise, were Moses and Aaron and his sons, guarding the sanctuary itself, to protect the people of Israel. And any outsider who came near was to be put to death. All those listed among the Levites, whom Moses and Aaron listed at the commandment of the LORD, by clans, all the males from a month old and upward, were 22,000.
And the LORD said to Moses, “List all the firstborn males of the people of Israel, from a month old and upward, taking the number of their names. And you shall take the Levites for me—I am the LORD—instead of all the firstborn among the people of Israel, and the cattle of the Levites instead of all the firstborn among the cattle of the people of Israel.” So Moses listed all the firstborn among the people of Israel, as the LORD commanded him. And all the firstborn males, according to the number of names, from a month old and upward as listed were 22,273.
And the LORD spoke to Moses, saying, “Take the Levites instead of all the firstborn among the people of Israel, and the cattle of the Levites instead of their cattle. The Levites shall be mine: I am the LORD. And as the redemption price for the 273 of the firstborn of the people of Israel, over and above the number of the male Levites, you shall take five shekels per head; you shall take them according to the shekel of the sanctuary (the shekel of twenty gerahs), and give the money to Aaron and his sons as the redemption price for those who are over.” So Moses took the redemption money from those who were over and above those redeemed by the Levites. From the firstborn of the people of Israel he took the money, 1,365 shekels, by the shekel of the sanctuary. And Moses gave the redemption money to Aaron and his sons, according to the word of the LORD, as the LORD commanded Moses.
(Numbers 3 ESV)
Fret not yourself because of evildoers;
be not envious of wrongdoers!
For they will soon fade like the grass
and wither like the green herb.
Trust in the LORD, and do good;
dwell in the land and befriend faithfulness.
Delight yourself in the LORD,
and he will give you the desires of your heart.
Commit your way to the LORD;
trust in him, and he will act.
He will bring forth your righteousness as the light,
and your justice as the noonday.
Be still before the LORD and wait patiently for him;
fret not yourself over the one who prospers in his way,
over the man who carries out evil devices!
Refrain from anger, and forsake wrath!
Fret not yourself; it tends only to evil.
For the evildoers shall be cut off,
but those who wait for the LORD shall inherit the land.
In just a little while, the wicked will be no more;
though you look carefully at his place, he will not be there.
But the meek shall inherit the land
and delight themselves in abundant peace.
The wicked plots against the righteous
and gnashes his teeth at him,
but the Lord laughs at the wicked,
for he sees that his day is coming.
The wicked draw the sword and bend their bows
to bring down the poor and needy,
to slay those whose way is upright;
their sword shall enter their own heart,
and their bows shall be broken.
Better is the little that the righteous has
than the abundance of many wicked.
For the arms of the wicked shall be broken,
but the LORD upholds the righteous.
The LORD knows the days of the blameless,
and their heritage will remain forever;
they are not put to shame in evil times;
in the days of famine they have abundance.
But the wicked will perish;
the enemies of the LORD are like the glory of the pastures;
they vanish—like smoke they vanish away.
The wicked borrows but does not pay back,
but the righteous is generous and gives;
for those blessed by the LORD shall inherit the land,
but those cursed by him shall be cut off.
The steps of a man are established by the LORD,
when he delights in his way;
though he fall, he shall not be cast headlong,
for the LORD upholds his hand.
I have been young, and now am old,
yet I have not seen the righteous forsaken
or his children begging for bread.
He is ever lending generously,
and his children become a blessing.
Turn away from evil and do good;
so shall you dwell forever.
For the LORD loves justice;
he will not forsake his saints.
They are preserved forever,
but the children of the wicked shall be cut off.
The righteous shall inherit the land
and dwell upon it forever.
The mouth of the righteous utters wisdom,
and his tongue speaks justice.
The law of his God is in his heart;
his steps do not slip.
The wicked watches for the righteous
and seeks to put him to death.
The LORD will not abandon him to his power
or let him be condemned when he is brought to trial.
Wait for the LORD and keep his way,
and he will exalt you to inherit the land;
you will look on when the wicked are cut off.
I have seen a wicked, ruthless man,
spreading himself like a green laurel tree.
But he passed away, and behold, he was no more;
though I sought him, he could not be found.
Mark the blameless and behold the upright,
for there is a future for the man of peace.
But transgressors shall be altogether destroyed;
the future of the wicked shall be cut off.
The salvation of the righteous is from the LORD;
he is their stronghold in the time of trouble.
The LORD helps them and delivers them;
he delivers them from the wicked and saves them,
because they take refuge in him.
(Psalm 37 ESV)
Something to Consider
Numbers 3: In order to more properly understand the purpose behind the numbering of the Levites and the numbering of the firstborn males among Israel, we must go back and remember what took place during the last plague in Egypt. The final plague in Egypt targeted the firstborn males throughout Egypt while 'passing over' and saving the firstborn males among Israel. Therefore, immediately following this plague and the exodus out of Egypt, the Israelites were commanded to consecrate every firstborn male to the Lord (Exodus 13). This meant firstborn cattle was to be dedicated for sacrifices and firstborn boys were to be dedicated in service to God and His sanctuary.
However, things later changed after Moses came down from Mount Sinai and saw the people worshipping the golden calf that they had made in his absence. Moses confronted the congregation of Israel and challenged them by saying, "Who is on the Lord's side? Come to me." And we are told that all the sons of Levi (Levites) stood with Moses (Exodus 32). Therefore, after ordering the sons of Levi to execute the idolaters among Israel, Moses declared that "Today you have been ordained for the service of the LORD, each one at the cost of his son and of his brother, so that he might bestow a blessing upon you this day."
The Levites had become holy substitutes who were set apart as holy priests who would serve as the representatives between God and man. Therefore, the Levites prefigured the ultimate Holy Substitute who serves as the Eternal High Priest and Righteous Representative between God and man - the man Christ Jesus.
The former priests were many in number, because they were prevented by death from continuing in office, but [Christ] holds his priesthood permanently, because he continues forever. Consequently, he is able to save to the uttermost those who draw near to God through him, since he always lives to make intercession for them. For it was indeed fitting that we should have such a high priest, holy, innocent, unstained, separated from sinners, and exalted above the heavens. He has no need, like those high priests, to offer sacrifices daily, first for his own sins and then for those of the people, since he did this once for all when he offered up himself. (Hebrews 7)
Christ is the fulfillment of the Levitical priesthood and therefore, the final High Priest of Israel. Just as the Levites redeemed the firstborn of Israel so Christ redeems all the firstborn of God.
Now it's worth noting that the total number of Levites was almost equal to the total number of the firstborn males among Israel that they had replaced. God in His perfect sovereignty numbers His people according to His plans and purposes. And the tribe that God set apart for His service ended up being the smallest tribe among Israel by far. God in His infinite wisdom works through the seemingly insignificant to impact the world significantly.