Pentecost, the Day God sends the Spirit afresh on God’s people, makes them the kind of people God wants them to be. Pentecost, as we turn to chp 10 of 40 Days Living the Jesus Creed is a promise. The promise of Pentecost or the promised Pentecost or Pentecost promse, it doesn’t matter — the two terms need to be connected.

Pentecost happened once, but Pentecost is also promise: promise that God will do the work that makes us the kind of people God wants us to be.
Pentecost, since it is God’s promise, is as good as God’s word. In 40 Days we look at God’s sure word with Abraham. So sure is God’s word that God entered between the split and divided animals to say, “If my word doesn’t come true, then do to me what we have done to these animals.” Such is the implication of this ceremony.
The drama of this event, surely not missed by the ancients, is that Abraham watched and waited and God did all the walking. Which means the promise God gave to Abraham is totally dependent upon God and upon the surety of God’s word.
The essential promise of the covenant is “I will be with you and you will be my people.” That is what Pentecost is: God is with us in the Spirit and we are to be God’s-indwellt-people.
That’s the Pentecost promise, as sure as God’s word.