Acts 1:4-8 (NKJV)
The Holy Spirit Promised
4 And being assembled together with them, He commanded them not to depart from Jerusalem, but to wait for the Promise of the Father, “which,” He said, “you have heard from Me; 5 for John truly baptized with water, but you shall be baptized with the Holy Spirit not many days from now.” 6 Therefore, when they had come together, they asked Him, saying, “Lord, will You at this time restore the kingdom to Israel?” 7 And He said to them, “It is not for you to know times or seasons which the Father has put in His own authority. 8 But you shall receive power when the Holy Spirit has come upon you; and you shall be [a]witnesses to Me in Jerusalem, and in all Judea and Samaria, and to the end of the earth.”
Luke 1:1-4 (NKJV)
Dedication to Theophilus
1 Inasmuch as many have taken in hand to set in order a narrative of those things which [a]have been fulfilled among us, 2 just as those who from the beginning were eyewitnesses and ministers of the word delivered them to us, 3 it seemed good to me also, having [b]had perfect understanding of all things from the very first, to write to you an orderly account, most excellent Theophilus, 4 that you may know the certainty of those things in which you were instructed.