Question:
“And it shall come to pass afterward, that I will pour out my spirit upon all flesh” (Joel 2:28 and Acts 2:17). Does this mean that non-Christians can have the Spirit?

Answer:
There is a key word in Joel’s prophecy which will help us to answer the above question. That word is “afterward.” Joel said, “It shall come to pass AFTERWARD.” After what? The answer to that lies in the first 27 verses of the chapter. Space forbids going over each verse, but allow me to give a brief summary. In verses 1-11 Joel gives a graphic description of “the day of the Lord.” Almost every O.T. prophet alludes to this time and in each case it is characterized by judgment. We see in Joel that God will use a great army (vs. 2, 5, 11) to execute judgment upon His people for their wickedness. In verses 12-17 we see Jehovah appealing to His people to humble themselves and to return unto Him. Then in verses 18-27 we see Jehovah, in response to His people’s cry for mercy, removing the army from them and blessing them materially with rain and plenty of food. It is at this point that Joel says, “It shall come to pass AFTERWARD (after the fulfillment of verses 1-27), that I will pour out My spirit upon all flesh.”

Two points must be stressed concerning this prophecy and they will both help us to understand who it is that receives the outpouring of the Spirit. (1) Joel’s prophecy relates to God’s earthly people, Israel (see vs. 1, 15-19 ,23, 26, 27), not to Christians. (2) Joel’s prophecy is yet future, for it involves Israel’s restoration to their land in unbelief, a great invasion from a northern army, and Jehovah’s intervention on their behalf which will result in untold blessings being bestowed upon them. This prophecy has nothing to do with the present dispensation where God is uniting Jews and Gentiles into one body (the Church) and fitting them for heaven.
Thus the outpouring of the Spirit (in Joel’s prophecy) has to do with a future day when Israel will once again be the object of God’s purposes. After the rapture of the church to heaven, God will cause His earthly people Israel to pass through a time of great tribulation (see Jeremiah 30:7; Daniel 12:1; Matthew 24:21) which will result in a remnant turning to Him in true repentance and faith. When the northern army (that Joel speaks of) invades the land, this remnant will cry out to the Lord and the Lord will then return to the earth in power and glory to save them from their enemies. After the destruction of their enemies, God will bless Israel in two ways: (1) Materially (Joel 2:21-26); and (2) Spiritually (2:28, 29). The pouring out of the Spirit is primarily upon the people in Israel (see Isaiah 32:15; 44:1-3; Ezekiel 36:27, 28; 37:14; 39:29), though it may include Gentiles who are to be blessed along with Israel in the Millennial reign of Christ.One more question remains. Why does Peter, on the day of Pentecost, quote from Joel’s prophecy, giving it some application to what took place on that day, when the Spirit was given to believers and they spoke in tongues? Before Peter actually quotes from Joel, he says, “But THIS is THAT which was spoken by the prophet Joel.” He did not say that it was a direct fulfillment of the events of Joel. When a prophecy was actually being fulfilled, the language is quite different from what we have here. (Such as: “That it might be fulfilled.” See Matthew 1:22; 2:15, 17; 8:17; 12:17; etc.) In saying, “THIS is THAT,” I believe Peter is simply calling attention to the fact that some things like THAT which took place on the day of Pentecost had been predicted by Joel. The same POWER of the Holy Spirit which was manifested in Peter’s day, will be manifested in the future when Israel is blessed at the Lord’s coming to the earth. Thus, what happened on the day of Pentecost was a SAMPLE of what Joel foretold, but it was not a literal fulfillment of it.