From the Lives of the Brethren:
The Chancellor of the University in Paris, having decreed [February 1256] that this same Brother Thomas should maintain his thesis publicly next day for the doctorate, that same night this brother beheld a figure come and stand before him with an open book in which were written the words: ‘Thou waterest the hills from above, the earth shall be filled with the fruit of thy works” (Ps. ciii 13). He therefore chose them for the text of his thesis.
From the Lives of the Brethren of the Order of Preachers 1206-1259, translated by Placid Conway, O.P., edited with notes and introduction by Bede Jarrett, O.P. (New York: Benziger Brothers, 1924) IV,23: page 196.
This story is recalled in the inaugural address of Father Brian J. Shanley, O.P. given at Providence college three years ago, on September 30, 2005, when he became the 12th President of Providence College. Fr. Shanley’s address begins:
“The story goes that when Thomas Aquinas was informed in the spring of 1256 that he had been chosen to assume the office of magister in sacra pagina at the University of Paris (“master of the sacred page” was the technical term for a theologian in those days), he immediately began to pray fervently about the theme of his inaugural lecture. The next night he experienced the apparition of a venerable Dominican-in one version St. Dominic himself-who answered his prayer by proposing the following line from Psalm 104:13 as his starting point: Rigans montes de superioribus suis: de fructu operum tuorum satiabitur terra (in those days Dominican apparitions spoke in Latin). An English rendering of the verse in your program reads: From thy high pavilion thou dost water the hills, the earth is enriched by thy provision. The first sentence of the lecture articulates a core conviction about divine providence that permeates Aquinas’s entire theological oeuvre and that I first learned as a student here: The king of the heavens, the Lord, established this law from all eternity: that the gifts of providence should reach what is lowest through intermediaries. God’s loving plan for creation is mediated by the ministry of creatures. Specifically, Aquinas argues that the human activities of teaching and learning, the heartbeat of this campus, are integral parts of divine providence, for it is through teaching and learning that we appropriate God’s own wisdom and thereby our happiness.”
A translation of St. Thomas Aquinas’s inaugural address can be found in the volume: Albert & Thomas: Selected Writings, translated, edited, and introduced by Simon Tugwell, O.P.; preface by Leonard E. Boyle, O.P. (New York: Paulist Press, 1988).