“You have permanently come (perfect tense) to Mount Zion, and to the city of the living God, the heavenly Jerusalem” (Hebrews 12:22a).
We have already arrived at the celestial city of Jerusalem. For it is not written that "we will come" or that "we may come," but rather that we have already come—and that permanently, since the Greek perfect tense is used there! How can this be? Because it is also written that we have already died, and our life has been permanently hidden with Christ in God (Colossians 3:3). And yes, the perfect tense is used there as well! Hallelujah! For though we are physically in this present world, we are also spiritually seated with Christ in the heavenly realms (Ephesians 2:6). Therefore, as Christians, we are commanded to seek the things above where Christ is, seated at the Father's right hand (Colossians 3:1-2). We are not earth-dwellers like those seen in Revelation (Revelation 13:8), but we are dwellers of Heaven. For truly, we are presently citizens of His heavenly kingdom (Philippians 3:20)—and our names are already written there (Luke 10:20).
Reminder: The Greek perfect tense speaks of a completed past action with ongoing, permanent results. The Blue Letter Bible app or website is great for learning these truths, especially if you are like me and have no formal training or form of higher education. In fact, I dropped out of high school and had an early speech impediment, yet by God's grace, I now teach, write, and even publicly (in person) speak. All the glory is His, and I'm thankful for His patience with me!