Numbers 20:8 Take the rod, and gather thou the assembly together, thou, and Aaron thy brother, and speak ye unto the rock before their eyes; and it shall give forth his water, and thou shalt bring forth to them water out of the rock: so thou shalt give the congregation and their beasts drink.
Here we have a great picture of the two advents of Christ. We know this because Paul tells us in 1 Cor. 10:4 that the Israelites "drank of that spiritual Rock that followed them: and that Rock was Christ." The passage in Exodus shows His first coming. Moses was told to "smite the rock." On the cross, Jesus was "smitten of God, and afflicted...wounded for our transgressions...bruised for our iniquities" (Isaiah 53:4-5). Because of this, we have access to "living water."
"But whosoever drinketh of the water that I shall give him shall never thirst; but the water that I shall give him shall be in him a well of water springing up into everlasting life." (John 4:14)
The second passage in Numbers tells of His second coming. Notice Moses is told to speak to the rock in order to produce the water. I think this aligns nicely with the idea that the remnant of Jews in the last days, having been broken by the "time of Jacob's trouble" and being without any other hope of deliverance, will petition Messiah to return and save them from destruction.
"Behold, your house is left unto you desolate: and verily I say unto you, Ye shall not see me, until the time come when ye shall say, Blessed is he that cometh in the name of the Lord." (Luke 13:35)
"For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in. And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob." (Romans 11:25-26)
"Alas! for that day is great, so that none is like it: it is even the time of Jacob's trouble; but he shall be saved out of it." (Jeremiah 30:7)
The Holy Spirit is very consistent in His use of the rock or stone throughout the Bible. I hope to explore this more in the future. For now I leave you with this:
"The LORD liveth; and blessed be my rock; and let the God of my salvation be exalted." (Psalm 18:46)