Key Points:
Peter’s failures and recovery made him a better Pope. (Don’t despair over your sins; repent and learn from them!)
Acts attributed to Luke, a “sequel” to Luke’s Gospel, could perhaps be called “the Acts of the Holy Spirit.”
v.18 See Session 33 (Mt. 27) for an explanation that should help to solve the discrepancy of these two accounts of Judas’ death.
v.21-25 Peter called for the new Apostle, and the way Matthias was chosen (casting of lots!) was based not on Scripture, but based on the new Church’s authority alone, as the keeper of the keys of the kingdom. (Mt. 16:17-20.) This rather strange method of choice was because the Holy Spirit had not yet descended on the Church, as will happen in Acts Chapter 2.
Catholic Doctrine Bible Study