1.  The day is fully come. The Holy Spirit, God the ply Spirit moves sovereignly as the Father directs. His timing is always precise and on time. We often feel there is nothing happening, a gap, or supposed silence befalls us, as it did for those 120, or the 430 years between Malachi and John the Baptist. Not a half measure, our heavenly Father  is precise in His timing. It is our act of worship/faith to accept this and anticipate something far beyond our own expectation. The word used is meant o be understood filled up completely, or fulfilled.
2. The word used to describe one accord in the King James and NKJV is the word  ὁμοθυμαδὸν homothymadon, with a single mind. They were all in agreement and single minded about obeying Jesus and awaiting the Holy Spirit. Any thoughts otherwise were not publicly entertained, or subsumed to the unity of the group. This is an imperative for the church. We must seek the Father’s will if the Holy Spirit can work within us unimpeded by pettiness, distractions, or unreigned pride.
3. They were gathered together in one place. (Can’t think of the meeting together passage. In other words, they were not scattered across in individual places, but come together (as shown in the previous chapter, to pray. Mat 18:20)

Sometimes we can only see this in hindsight. This is the relationship of faith in the believer, to step out, not desiring a “fleece” – some sign that we ask of God as to direction, but rather stepping out KNOWING that if the doors are open we go through. And usually, they do. If not, then we chalk the experience up to a no, or wait, I have something better response from our Heavenly Father.

The countries themselves form a compass around Israel on the Mediterranean.

It was common practice of the day at Synagogue, to include a reading of the mighty works of God; the Red Sea crossing, leading out of Egypt, and other victories given the Jews. In fact, it is often our most powerful testimony, to speak of the mighty works of God in our own lives. They may dispute the Bible, or the Gospel, but they cannot refute your personal testimony!

Authentication is the way we show we are the person we say we are to someone who doesn’t know us. Almost all of us use passwords or scanners, etc. to prove who we are to people who don’t know who we are. This is precisely why Jesus performed the miracles, many unique, restoring vision (John 9:32) to authenticate He was who He claimed to be,  so that if you chose (choose now) to reject that claim, you did(do) so willfully ignoring the facts.

The Scripture Peter quotes he explains: