Read Hebrews 12:22-24. What does Paul describe here?

 Hebrews affirms that we have come to Mount Zion and participate in a great celebration. “But you have come to Mount Zion and to the city of the living God, the heavenly Jerusalem, and to innumerable angels in festal gathering” (Heb 12:22, ESV). We have come through faith in the person of our representative, Jesus. In this celebration we find an innumerable host of angels, God Himself, and Jesus, who is the center of the celebration. We come as part of the “assembly of the firstborn who are enrolled in heaven” (Heb. 12:23, ESV). Our names are enrolled in the books of heaven, where God’s professed people are listed (Exod. 32:32, Ps. 56:8, Dan. 12:1, Mal. 3:16, Luke 10:20, Rev. 13:8, Rev. 17:8).

 We are the “firstborn” because we share the inheritance of the Firstborn par excellence, Jesus (Heb. 1:6). Thus, we have come not as guests but as citizens (compare with Phil. 3:20). We are also described as “the spirits of the righteous made perfect” (Heb. 12:23, ESV). This expression is a figure of speech in which a dimension of our human nature stands for the whole. It is analogous to the expression “the Father of spirits” in Hebrews 12:9, which refers to God as the Father of us all, human beings who are spiritual in nature.

 The festal gathering celebrates the inauguration of Jesus’ kingly rule, priestly ministry, and the inauguration of the new covenant. In Hebrews, Mount Zion is the place where all these events take place. Three of the psalms in Hebrews 1:5-14 describe the enthronement of the Son and have Mount Zion as the place where it occurred (Ps. 2:6, 7; Ps. 110:1, 2; Ps. 102:21-27).

 Mount Zion is also the place where the Son was appointed “priest forever” (Heb. 5:6), a quotation of Psalm 110:4. According to Psalm 110, the appointment of the Son as High Priest occurs at Mount Zion, as well (Ps. 110:2). Finally, Hebrews argues that the inauguration of Jesus’ priesthood also marks the inauguration of the new covenant (Heb. 7:11-22). Thus, Mount Zion is also the place where the new covenant was ratified. Hebrews 12:22-24 describes, then, the festal gathering that occurred in heaven when Jesus ascended.