Looking for a theological definition in Webster is problematic. Why not look to the Bible? The are two places where the ESV translates the Greek using the word "regeneration"--Matthew 19:28 and Titus 3:5. The Matthew passage is fairly irrelevant to this discussion, but the Titus passage is not. Titus says:
[5] he saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit, [6] whom he poured out on us richly through Jesus Christ our Savior, [7] so that being justified by his grace we might become heirs according to the hope of eternal life. (Titus 3:5–7 ESV, emphasis mine)This word "regeneration" is παλιγγενεσία, which is a compound word meaning--literally--born again. In this passage, the main verb is "He saved us." If you go back to your gradeschool days and do a bit of diagramming, you'll see that the subject here is "God" and "He" is doing the saving. Why is He doing the saving? He's merciful. How is He doing the saving? "By the washing of regeneration and renewal of the Holy Spirit."
So, it is clearly the work of God to both regenerate and renew us. This is perfectly in-step with Jesus' words to Nicodemus in John 3 where Jesus tells him, "You must be born again." Being born again is not something we can do for ourselves; it must be done to us.
In point of fact, the "you" in verse 31 (of Luke 22) is indeed plural... so the sifting is of more than Peter. However, the "you"s in verse 32 are singular and are referring to Peter alone.
The sentiment here is just fine, but it is based on bad exegesis of the passage...
The Archangel
Question relative to ἐπιστρέψας
I notice W&H translates that word as - having - beturned - upon
Does not that translation imply and or state, God is the One who is doing the turning? Maybe by the abundantly shedding of the Holy Spirit?
http://lexiconcordance.com/greek/1994.html