Acts 1:4, 8

While being together and eating with them, He commanded them not to leave Jerusalem, but to wait for what the Father had promised, “Of which,” He said,“you have heard Me speak. [John 14:16, 26; 15:26]

But you will receive power and ability when the Holy Spirit comes upon you; and you will be My witnesses [to tell people about Me] both in Jerusalem and in all Judea, and Samaria, and even to the ends of the earth.”