Homily 1, Acts of the Apostles
The former account I made, O Theophilus, of all that Jesus began both to do and teach,
until the day in which He was taken up, after He through the Holy Spirit had given commandments to the apostles whom He had chosen,
to whom He also presented Himself alive by many infallible proofs, being seen by them during forty days and speaking of the things pertaining to the Kingdom of God.
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;"
for John truly baptized with water, but you shall be baptized with the Holy Spirit not many days from now."
This is a letter to a "lover of God;" the first few verses sum of the previous letter: all that Jesus began to do and teach until the day that he was taken up. Luke summarizes the end of his previous letter-- Christ gave commandments to the apostles, presented Himself alive, and then assembled them together in Jerusalem with a promise of the coming of the Holy Spirit.
The first commandment in this book is to wait. To wait for the coming of the Holy Spirit.
Chrysostom's sermon begins with a reflection on the importance of the Book of Acts. It is replete with Christian wisdom and sound doctrine, especially pertaining to the Holy Spirit. This book shows how Christ's predictions in the Gospel about the apostles' lives would come to pass. And it is the "crowning point of our salvation" for both Christian practice and doctrine. Finally, this book demonstrates Christian evangelistic strategy: first, to proclaim Christ's divinity, death and Resurrection; and to move to doctrine about the Godhead from there.
Of evangelistic strategy, Chrysostom says:
"Therefore it is that gently and little by little [the apostles] carry [the evangelized] on, with much consideration and forbearance letting themselves down to their low attainments, themselves the while obtaining in the more plentiful measure the grace of the Spirit, and doing greater works in Christ's name than Christ Himself did."
Acts, says Chrysostom, is a demonstration of the Resurrection: "this being once believed, the rest [of Christian faith] would come in due course."
He also makes much of the importance of eyewitness:
"Upon this [Apostolic] ground we also argue with unbelievers. For if He did not rise again, but remains dead, how did the Apostles perform miracles in His name? But they did not, say you, perform miracles? How then was our religion instituted? ... For this would be the greatest of miracles, that without any miracles, the whole world should have eagerly come to be taken in the nets of twelve poor and illiterate men."
Chrysostom also emphasizes the forty days of Christ's life before his Ascension: Christ remained so that his disciples would see "Him in His own proper Person." Christ commanded them to stay in Jerusalem because he didn't want them fighting before being armed with the Spirit. And Christ made them wait for the Spirit until after He Himself had ascended so that they would miss His presence keenly and expect the Spirit earnestly.
Whereas the Gospels, says Chrysostom, are a history of what Christ did and said, the Acts are histories of what the Comforter did and said. And so he makes much of the synergy in our lives with the work of the Holy Spirit:
"We shall be surest of obtaining God's mercy when we do our part."
"Which is best, to fear or to labor?"
The conclusion of the sermon is both a reminder of the great expectations put to Christians, and an exhortation to not let this responsibility keep one from baptism. For where the responsibility increases, so does God's mercy increase.