This post will briefly and partially expound 2 Peter 3.8: that a single day is like a thousand years with the Lord and a thousand years are like a single day.
Peter in the context expounds several “days” which deserve careful consideration. The primary reference is the return of Christ in the “Day of The Lord”in vs. 7. Scoffers were focused on their expectation that Judgment spoken about so often in the Old testament was not arriving when they thought it should appear. Another use of “day” concerns the eternal state in the very last verse.
In our verse (8) Peter says that a “day” in God’s sight was like a thousand years to us humans. This comes from Psalm 90, the great Psalm of Moses. Notice vs. 4: A thousand years in your sight are like a day that has just gone by, or like a watch in the night. This means that God’s capacity is much greater than humans’ capacity.
Peter recognizes also from the scriptures that God works in each and all human situations simultaneously. He is omnipresent. This is most likely what “everyday as a thousand years” means. Humans are not efficient multitaskers, and even if some folks think they are multitaskers, none are perfectly. Hosea 14.9b seems to give this sense: for the ways of the Lord are right and the upright walk in them, but transgressors stumble in them. So Hosea says the Lord’s superintendence extends to every human action of life whether the righteous are blessed or the wicked punished in their own transgression during earthly life.
So how does this affect the eternal state? Since God is changeless, He continues in His vast capacity to interact with us and others. What will we do in heaven? A hint may be found in Mt. 22.30: For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven. We know from Hebrews 1.7: Of the angels he says,“He makes his angels winds, and his ministers a flame of fire.” So, it may be that further ministries will be given to us in our then resurrected bodies. All these ideas and more await the saints, and therefore, heaven will not be boring.