by St. John Chrysostom
But why did the Holy Ghost come to them, not while Christ was present, nor even immediately after his departure, but, whereas Christ ascended on the fortieth day, the Spirit descended "when the day of Pentecost," that is, the fiftieth, "was fully come?" (Acts ii. 1.) And how was it, if the Spirit had not yet come, that He said, "Receive ye the Holy Ghost?" (John xx. 22.) In order to render them capable and meet for the reception of Him. For if Daniel fainted at the sight of an Angel (Dan. viii. 17), much more would these when about to receive so great a grace. Either this then is to be said, or else that Christ spoke of what was to come, as if come already; as when He said, "Tread ye upon serpents and scorpions, and over all the power of the devil." (Luke x. 19.) But why had the Holy Ghost not yet come? It was fit that they should first be brought to have a longing desire for that event, and so receive the grace. For this reason Christ Himself departed, and then the Spirit descended. For had He Himself been there, they would not have expected the Spirit so earnestly as they did. On this account neither did He come immediately after Christ's Ascension, but after eight or nine days. It is the same with us also; for our desires towards God are then most raised, when we stand in need.