The following quotation is not the one that I was going to use but it struck me as one of those points which the Holy Father makes so simply and well. (The phrase mens concordet voci could be translated as "let the heart/mind be in accord with the voice.") Speaking of the priest celebrating Mass, he says:
He is in a conversation with God because the texts of Holy Mass are not theatrical scripts or anything like them, but prayers, thanks to which, together with the assembly, I speak to God.
It is important, therefore, to enter into this conversation. St Benedict in his "Rule" tells the monks, speaking of the recitation of the Psalms, "Mens concordet voci". The vox, words, precede our mind. This is not usually the case: one has to think first, then one's thought becomes words. But here, the words come first. The sacred Liturgy gives us the words; we must enter into these words, find a harmony with this reality that precedes us.