The spirit of God came on the disciples in the Upper Room on the Day of Pentecost, fifty days after their Lord's crucifixion. It was a Saturday morning at 11:59 A.M.
Or, perhaps in was ten minutes past noon. It doesn't matter. The point is that it came SUDDENLY. There was a look, a sound, the sensation of movement against the skin, realization, knowledge, the utterances of different languages.
Thus will the New Covenant begin.