In his Rule, Saint Benedict coined the formula Mens nostra concordet voci nostrae--our mind must be in accord with our voice (Rule 19, 7). Normally, thought precedes word. But praying the Psalms and liturgical prayer in general is exactly the other way round: The word, the voice, goes ahead of us, and our mind must adapt to it. For on our own we human beings do not "know how to pray as we ought" (Romans 8:26)--we are too far removed from God, he is too mysterious and too great for us. And so God has come to our aid: He himself provides the words of our prayer and teaches us to pray. Through the prayers that come from him, he enables us to set out toward him; by praying together with the brothers and sisters he has given us, we gradually come to know him and draw closer to him.

In Saint Benedict's writings, the phrase cited just now refers directly to the Psalms, the great prayer book of the People of God of the Old and New Testament. The Psalms are words that the Holy Spirit has given to men; they are God's spirit become word. We thus pray "in the Spirit," with the Holy Spirit. This applies even more, of course, to the Our Father. When we pray the Our Father, we are praying to God with words given by God, as Saint Cyprian says.

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Again and again, each one of us with his mens, his own spirit, must go out to meet, open himself to, and submit to the guidance of the vox, the word that comes to us from the Son. In this way his own heart will be opened, and each individual will learn the particular way in which the Lord wants to pray with him.

(Benedict XVI, Jesus of Nazareth, pp 131, 133)