Yesterday's collect was a prayer to God our Father that the Spirit He sent on His Church to begin the teaching of the gospel continue to work in the world through the hearts of all who believe.
The Spirit blows wherever He wills, so why does He usually seem to will to blow through the hearts of all who believe, instead of directly on the places in need of justice or faith? If He can appear as tongues of fire over the heads of the Apostles, why not go ahead and do the same over everyone's head?
We can answer such questions in a more or less convincing fashion, but whatever we come up with, we're still left with the fact that this is how the Holy Spirit prefers to operate. That is, we're still left praying that the Holy Spirit continue to work in the world through our own hearts, even in Ordinary Time.