But of that day and hour knoweth no man, no, not the angels of heaven, but my Father only. – Matthew 24:36

In the olden times, when men raised cairns to the memory of departed kings, it was usual to put a heap of stones over the tomb, and every passer-by threw another stone. In course of age. those mounds grew into small hills. Now the Church of Christ in the present day is growing something in that way. Each Christian converted to Christ throws his stone; we each do our measure. By the grace of God let us each make sure of one stone being deposited there, and strive to add another by laboring to be the instruments of bringing someone else to Christ; in this way the Church will grow; and as year after year rolls on, each Christian serving his Master, the Church will increase; and it shall come to pass in the last times, that even by the efforts of Christ’s people, owned by God the Holy Spirit, this mountain shall be highly exalted in the midst of the hills.

We must fight on day-by-day and hour-by-hour; and when we think the battle is almost decided against us, we shall hear the trump of the archangel, and the voice of God, and He shall come, the Prince of the kings of the earth: at His name, with terror they shall melt, and like snow driven before the wind from the bare side of Salmon shall they fly away; and we, the Church militant, trampling over them, shall salute our Lord, shouting, “Hallelujah, hallelujah, hallelujah, the Lord God Omnipotent reigneth.” ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0249.cfm