David was stalked by death from early youth; a lion, a bear, Goliath, King Saul, his son Absalom and others all tried to kill him.
But David did not die, could not die, until ... (Acts 13:36) only after David had served God's will and purpose and counsel in his own generation, he died and was buried with his forefathers.
We, too, who are the redeemed heirs of salvation, are immortal until we reach that stage which David reached.
During our sojourn here on Planet Earth, the Creator is re-creating. God no longer creates, no longer makes something out of nothing. Now He is recreating, restoring, changing us from glory to glory (2 Corinthians 3:18) as God works to re-create the Divine image in us, which was so horribly defaced by the Fall. (Defaced but not erased). God's building project within us will go on until we see Jesus and then we will be like Him in full restoration. While the work is going on in us on earth, an eternal and joyous and fulfilling work is being prepared for us in Heaven; for us to serve in the immediate Presence of the Living God. At the appointed time our presence will be required in Heaven.
Away back in the very early days, Job knew that our months are allotted (Job 14:5). The Psalmist reminds us that all our days are written in God's book before there was even the first of them (Psalm 139:16). Illness, etc. may be the access door to take a believer to the river which is between Planet Earth and the celestial shores but it is all in the plan and timing of God. Angels wait to take the Christian from the river and bring him/her to Glory. Then Jesus, Who is seated on the right hand of the Father, will stand to welcome His precious child home (Acts 7:56).
No believer will ever go through the Valley of Death, where Jesus went and conquered. We only go through the Valley of the Shadow (Psalm 23:4).
Heaven is not an airy-fairy, static place. We will continually grow in our fellowship with God and our knowledge of God through all eternity. How could we quickly grasp the wonder of the Godhead? We will learn, travel, work joyously without pressure or weariness. We will rule and reign with Christ as priests and kings; we will judge angels (I Corinthians 6:3). We will not be playing harps or picking flowers. We will serve God and see Him face-to-face (Revelation 22:3-5). We'll be busier than we've ever been; our work will be perfect and we'll never be tired.
God has given us a desire to accomplish, to achieve goals and we'll have continual pleasure in the satisfaction of jobs well done as we fulfill our God-give inheritance.
Music will fill Heaven. Christina Rosetti said that Heaven is revealed to earth as the homeland of music.
The most joyous composers have been vital Christians such as Bach and Handel. Music .. Service .. Worship.
The highest activity in Heaven will be our spontaneous and unrestrained adoration and worship to the triune God.