...and all nations shall flow unto it. And many people shall go and say, Come ye, and let us go up to the mountain of the LORD- Isaiah 2:2, 3

Once in the year all the people of Israel were wont to go to the little hill of Zion; and now, once for all, you see, not Israel, but all the nations of the earth coming to this great hill of Zion, to worship the Most High God.

I beg you carefully to observe the figure. It does not say they shall come to it, but they shall “flow unto it.” Understand the metaphor. It implies first their number. Now our churches are increased, converts drop into the churches; drop after drop the pool is filled. But in those days they shall flow into it; now it is but the pouring out of water from the bucket; then it shall be as the rolling of the cataract from the hillside, it shall flow into it. Now our converts, however numerous, are comparatively few, but then a nation shall be born in a day. The people shall renounce their gods at once. Whole nations shall of a sudden by an irresistible impulse flow into the Church, not one by one, but in one vast mass. The power of God shall be seen in bringing whole nations into the Church of God. You have seen the river flowing onward to the sea, with its banks all swollen, bearing its enormous contribution to the boundless ocean. So shall it be in the last days; each nation shall be like a river, rolling towards the foot of this great mountain, the Church of the living God. Happy, happy, happy day, when all the nations of the earth, with their multitude of tongues, shall flow into the mountain of God! ~ C.H. Spurgeon

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