'Beginning' in the Bible

but this is [the beginning of] what was spoken of through the prophet Joel:

Then Philip spoke and beginning with this Scripture he preached Jesus to him [explaining that He is the promised Messiah and the source of salvation].

But Peter began [at the beginning] and explained [the events] to them step by step, saying,

When I began to speak, the Holy Spirit fell on them just as He did on us at the beginning [at Pentecost].

Says the Lord,Who has been making these things known from long ago.

Now much time had been lost, and navigation was dangerous, because even [the time for] the fast (Day of Atonement) was already over, so Paul began to strongly warn them,