When the Bible refers to the sealing work of God, there are two categories: the first is the eternal sealing of specific persons including Jesus, Born Again Believers, and Believing Jews; the second refers to God's mysteries which remained sealed until a time appointed by God that they should be revealed. All that God seals, belongs to Him!
* "And the vision of all is become unto you as the words of a book that is sealed, which men deliver to one that is learned, saying, Read this, I pray: and he answers, I cannot; for it is sealed" (Isa. 29:11).
* "And he said, Go thy way, Daniel: for the words are closed up and sealed till the time of the end" (Dan. 12:9).
* "Labor not for the meat which perishes, but for that meat which endures unto everlasting life, which the Son of man shall give unto you: for Him has God the Father sealed" (Jn. 6:27).
Born Again Believers -
* "Now He Who establishes us with you in Christ, and has anointed us, is God; Who has also sealed us, and given the earnest of the Spirit in our hearts" (2 Cor. 1:21-22).
* "In Whom you also trusted, after that you heard the Word of Truth, the Gospel of your salvation: in Whom also after that you believed, you were sealed with that Holy Spirit of promise" (Eph. 1:13).
* "And grieve not the Holy Spirit of God, whereby you are sealed unto the day of redemption" (Eph. 4:30).
The Book of Seven Seals -
* "And I saw in the right hand of him that sat on the throne a book written within and on the backside, sealed with seven seals" (Rev. 5:1).
The 144,000 Jewish believers (see note below) -
* "Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads. And I heard the number of them which were sealed: and there were sealed an hundred and forty and four thousand of all the tribes of the children of Israel. Of the tribe of Juda were sealed twelve thousand. Of the tribe of Reuben were sealed twelve thousand. Of the tribe of Gad were sealed twelve thousand. Of the tribe of Aser were sealed twelve thousand. Of the tribe of Nepthalim were sealed twelve thousand. Of the tribe of Manasses were sealed twelve thousand. Of the tribe of Simeon were sealed twelve thousand. Of the tribe of Levi were sealed twelve thousand. Of the tribe of Issachar were sealed twelve thousand. Of the tribe of Zabulon were sealed twelve thousand. Of the tribe of Joseph were sealed twelve thousand. Of the tribe of Benjamin were sealed twelve thousand" (Rev. 7:3-8).
Note: See Revelation 14:1-5, which says:
* "And I looked, and, lo, a Lamb stood on the mount Sion, and with Him an hundred forty and four thousand, having His Father's name written in their foreheads. And I heard a voice from heaven, as the voice of many waters, and as the voice of a great thunder: and I heard the voice of harpers harping with their harps: and they sung as it were a new song before the throne, and before the four beasts, and the elders: and no man could learn that song but the hundred and forty and four thousand, which were redeemed from the earth. These are they which were not defiled with women; for they are virgins. These are they which follow the Lamb whithersoever He goes.
These were redeemed from among men, being the firstfruits unto God and to the Lamb. And in their mouth was found no guile: for they are without fault before the throne of God."