The Church Age will have an amazing supernatural end at the Rapture. The Church similarly had a spectacular beginning on the Day of Pentecost. Since Pentecost was when the Holy Spirit first began indwelling believers, this event was dramatic being described as "a rushing mighty wind" and "appeared to them [as] divided tongues, as of fire" causing people to speak in languages foreign to them (Acts 2:2-4).
The Apostle Peter quoted Joel 2:28 to explain what happened on the Day of Pentecost, "it shall come to pass in the last days, says God, that I will pour out of My Spirit on all flesh; your sons and your daughters shall prophesy, your young men shall see visions, your old men shall dream dreams" (Acts 2:17). In context, this is referring to the return of Jesus, "the coming of the great and awesome day of the Lord" (Acts 2:20 & Joel 2:31).
The fact that it has been almost 2,000 years and Jesus has not returned might lead some to think that Peter was wrong. But if you go back to Joel to see what he was talking about, the Prophet Joel characterized the pouring out of the Spirit of God in two phases: "Be glad then, you children of Zion, and rejoice in the Lord your God; For He has given you the former rain faithfully, And He will cause the rain to come down for you; the former rain, and the latter rain in the first month" (Joel 2:23).
Now Joel 2:23 is referring to literal rain. God blessed Israel with rains in the Spring and the Fall. Israel was having a drought at the time this was written and was looking forward to the prosperity that came from more abundant rain. But the context here reveals a prophetic aspect to the pouring out of God's Spirit. Here we see God talking about pouring out rain as a symbolic reference to pouring out His Spirit. As God promised to bless Israel with early and latter rain, He also promised them to pour out His Spirit in two separate phases. He poured out the early rain of His Spirit on Pentecost when the Holy Spirit began indwelling followers of Christ.
The latter rain will be when God pours out his Spirit on the nation of Israel as represented by the 144,000 of Revelation 7 and 14. While this is a promise to the nation of Israel, there is a principle here that applies to the Church. The Church began with God pouring out His Spirit on Jewish Christians, then God also poured out His Spirit on the Gentiles as well (see Acts 10:45). So we should expect God to likewise pour out His Spirit on all nations at the end of the Church Age as God prepares to work through Israel again. Jesus established this principle of prophetic developments foreshadowing the events of the Tribulation when He spoke of birth pangs in the Olivet Discourse.
God has begun pouring out His Spirit on all nations. When I was at Texas Instruments, I met a man through our Bible study group there who was born in Indonesia, a Muslim country. It goes without saying that missionaries are not exactly encouraged in Islamic countries. But this does not limit God. My coworker from Indonesia came to Christ as a result of Jesus appearing to him in a vision. He became an engineer to facilitate his immigration to the U.S. because Indonesia was not exactly friendly to Christians. Since I've heard the testimony of my coworker, I've heard many other testimonies of Muslims from various places converting to Christianity by direct revelation. And there is also this recent article documenting the phenomenon of Muslims converting to Christianity as a result of personally seeing a vision of the Savior.
The supernatural pouring out of God's Spirit is a clear sign we are in the season of the Jesus returning. This should cause followers of Christ to get on with doing what God is calling them to do and provoke those who are agnostic toward Jesus to get off the fence. The Church Age is coming to a close and the end will be spectacularly supernatural. People who witness the Rapture will have two clear choices: (1) believe the Bible by embracing Jesus Christ to be saved, or (2) embrace the lie explaining away the Rapture to get their wish of spending eternity separated from their Creator. As for "me and my house, we will serve the Lord" (Joshua 24:15).