Acts 10: Worldwide
Christianity took the first step to becoming an international movement in Acts 10. Cornelius, a Roman centurion, was given a vision where he was told to call for Peter. Peter was also given a vision where God told him it was permissible to eat different animals that were traditionally forbidden for Jews because what God has cleansed, people should not forbid.
The implication then was when Peter came to the house of Cornelius, he realized that God had been using the previous vision to demonstrate his mission.
Act 10:34 Then Peter opened his mouth, and said, Of a truth I perceive that God is no respecter of persons:
Act 10:35 But in every nation he that feareth him, and worketh righteousness, is accepted with him.
This is of course the logical implication of the Great Commission. If Jesus told people to preach the gospel in all the world, then it makes a lot of sense that the gospel would be available for the entire world, but that was somewhat revolutionary for the Jewish believers. After all, the Temple had areas that Gentiles were not able to enter. The idea that God was able to accept people of all nations was somewhat difficult for people raised in that particular culture.
However, this actually harkens all of the way back to Abraham. God promised that all the nations of the world would be blessed through his family. Through Jesus, a Jewish man and a descendent of Abraham, all the nations of the world were indeed blessed.
The criteria are the same for everyone. They need to fear God and this is through faith. It needs to be a true conversion in that the natural consequence of a relationship with God which is good work comes out. It doesn’t matter where you are in the world, but it does matter that you make the right choice.