A powerful passage, and a key to Revival

This is one of my favorite passages in the Bible:
Acts 4:²¹So when they had further threatened them, they let them go, finding nothing how they might punish them, because of the people: for all men glorified God for that which was done.
²²For the man was above forty years old, on whom this miracle of healing was shewed.
²³And being let go, they went to their own company, and reported all that the chief priests and elders had said unto them.
²⁴And when they heard that, they lifted up their voice to God with one accord, and said, Lord, thou art God, which hast made heaven, and earth, and the sea, and all that in them is:
²⁵Who by the mouth of thy servant David hast said, Why did the heathen rage, and the people imagine vain things?
²⁶The kings of the earth stood up, and the rulers were gathered together against the Lord, and against his Christ.
²⁷For of a truth against thy holy child Jesus, whom thou hast anointed, both Herod, and Pontius Pilate, with the Gentiles, and the people of Israel, were gathered together,
²⁸For to do whatsoever thy hand and thy counsel determined before to be done.
²⁹And now, Lord, behold their threatenings: and grant unto thy servants, that with all boldness they may speak thy word,
³⁰By stretching forth thine hand to heal; and that signs and wonders may be done by the name of thy holy child Jesus.

Why do I love this passage? Because of the results that it got:

³¹ And when they had prayed, the place was shaken where they were assembled together; and they were all filled with the Holy Ghost, and they spake the word of God with boldness.
³² And the multitude of them that believed were of one heart and of one soul: neither said any of them that ought of the things which he possessed was his own; but they had all things common.
³³ And with great power gave the apostles witness of the resurrection of the Lord Jesus: and great grace was upon them all.

A story of Amazing Revival. But how did this happen? Lets dissect the elements:
Verse 21: Threats from the authorities. This is what Jesus had endured. And they stated to the authorities that they weren't going to stop preaching Jesus. And yes... preaching JESUS is the key.
Verse 23: They told their fellowship about the coming persecution.
Verses 24-26: Quoting the word, the prophecy of David in the 2nd Psalm. You have to have the word of God if you want Revival.
Verses 27-28: Bringing the word to bear on your situation. Showing that the word applies to you, now.
Verses 29-30: These are the kickers. The Apostles do what Hezekiah did. Remove themselves from the situation, humble themselves and show that they are not involved, but that they are simple tools in the hands of their God. The authorities are not opposing THEM, they are opposing GOD. And what's more, is that the Apostles take it for granted that they aren't going to back down, aren't going to shirk... they simply ask for BOLDNESS in speaking the word, and GOD'S POWER: Not for themselves, not for their egos, not for anything except for God's glory. And of course that all this would be done in the name of JESUS, the name above all other names.

The proof is in the pudding. What happened? The place was shaken. The requests were honored. EVERYONE was filled with the Holy Ghost. The word of God was spoken with BOLDNESS. Everyone had unity. Great Grace was upon them all. Miracles and signs and wonders were done!

This is one of the most powerful prayers in the Bible. And I think the key is all in verses 29-30.