I Chronicles 23-26 -
When David got to be an old man, he made his son, Solomon king over Israel. At the same time he brought together the leaders of Israel, the priests and the Levites.
David then divided the Levites into groupings named after the sons of Levi: Gershon, Kohath, and Merari....From now on the assigned work of the Levites was to assist Aaron’s sons in the work of worship in God’s house.
The family of Aaron was grouped as follows as his sons Eleazar and Ithamar filled the office of priests. It turned out that there were more leaders from Eleazar’s family than in Ithamar’s so they divided them proportionately: 16 clan leaders from Eleazar’s family and 8 clan leaders from Ithamar’s family.
Next David and the worship leaders selected some from the family of Asaph, Heman, and Jeduthun for special service in preaching and music. The teams of security guards were from the family of Korah...Other Levites were put in charge of the financial affairs of the Temple of God.
Revelations 7 -
Immediately, I saw 4 Angels standing at the four corners of the earth, standing steady with a grip on the four winds so no wind would blow on the earth or sea, not even rustle a tree.
Then I saw another Angel rising from where the sun rose, carrying the seal of the Living God. He thundered to the 4 angels ...”Don’t hurt the earth!...until I’ve sealed the servants of our God on their foreheads!” I heard the count of those who were sealed, 144,000....I looked again. I saw a huge crowd, too large to count. Everyone was there...And they were standing, dressed in white robes and waving palm branches, standing before the Throne and the Lamb and heartily singing....All who were standing around the Throne--Angels, Elders, Animals--fell on their faces before the Throne and worshiped God singing...
Then an Elder told me, “These are those who come from the great tribulation, and they’ve washed their robes, scrubbed them clean in the blood of the Lamb. That’s why they are standing before God’s Throne. They serve him day and night in his Temple. The One on the Throne will pitch his tent there for them: no more hunger, no more thirst, no more scorching heat. The Lamb on the Throne will shepherd them, will lead them to spring waters of Life. And God will wipe every last tear from their eyes.”