ACTS 2:21 "And it shall come to pass, that whosoever shall call on the name of the Lord shall be saved."
There is never a lack of God's Spirit when Christ is exalted and this Gospel is preached. The disciples were commanded to preach the Gospel to every creature, so the ability to preach was given to them. Here were gathered people from all parts of the world and every walk of life. Some religious and some not. Some knowing God and some ignorant. Some came to worship and some were just curious. Some old, some young. But when they heard this Word preached in the power of God's Spirit, it was spoken in a way they could all understand. When God is going to save you, He will bring you where His Spirit is poured out through the preaching of the Gospel. God brings you to hear the Gospel, and He will use this hearing to save your soul.
God chose the weak and foolish things of this world to confound the wise and mighty. They did not hear these men speak concerning how they dressed or wore their hair, but they spoke of the "wonderful works of God." This is the Gospel. The Gospel reaches to all, covers every situation, gives the solution to every problem. They spoke of Christ and redemption through His blood. When this Gospel is preached it will be as strange to our ears as though it were a foreign language. These learned men were so ignorant they did not know these were real languages, but, Peter stood up and lifted up his voice as one who was truthful and convinced, not as one who tells lies. He told them that what they were seeing is only what had been promised and prophesied. This is a fulfilling of the Scriptures and the result of Christ's resurrection and ascension. This is the evidence that the kingdom of Heaven is come. Peter never departed from "thus sayeth the Scriptures." God's preachers never learn any more than what the Scriptures say, and the Spirit of God will never lead you to do anything not found in the Scriptures.
He told them that this is the time of the Gospel for you. This is the day of your grace. This is the time God has established for you. "Now is the accepted time, behold now is the day of salvation." Judgment is coming on you who deny this Gospel. If you do not fall down and worship Christ, you will fall under His wrath. But "whosoever shall call upon the name of the Lord shall be saved." Those who are saved, turn from themselves and call out to the Lord.
The promise is still the same. The message is still the same. The Messiah is still the same. God is still the same. His Judgment is still the same. Heaven is still the same. Holiness is still the same. Hell is still the same. Sin is still the same. Our need of a Saviour is still the same. This is the only way of Salvation for our souls. "Our hope is built on nothing less than Jesus' blood and righteousness."
"And it shall come to pass, that whosoever shall call on the name of the Lord shall be saved."