Question Six of Chapter Nine of the Third Decade
Whether observation of a time for doing something is lawful
It is asked whether it is lawful to observe times for doing something.
The response is given through two doctors.
The first is Lord Peter of Tarentaise, afterward Pope Innocent V, in Book IV of his commentary on the Sentences, distinction 23, article 4, who says that the observation of times is threefold.
One kind is superstitious or impious, as in those who observe the time of acts which are subject to free choice and begin actions under such a sign of the heavens. Persons of this kind are reproved in Isaiah 47: “Let the augurs of the heavens stand and save you, those who contemplated the stars and calculated the months.”
Another is an observation of shrewdness and foresight in those who observe the quality of the time in order to obtain an abundance of things and exclude want. This is neither reproved nor praised. Ecclesiasticus 33: “Why does day surpass day, and again light surpass light, and year surpass year? By the sun.”
Another observation of times is one of piety and devotion in good Christians who observe feast days, on which they judge that more time should be devoted to God than on other days because of the benefits especially conferred on that day or feast. The Apostle says in Romans 14: “One distinguishes one day from another.”
The second doctor is Lord Alexander of Hales in the Second Part of the Summa, question 3, article 9, who says that some things occur by a natural course and some by a voluntary course.
Therefore, in the first way, to observe a time for doing something which is caused by the natural constitution of the elements and of the time is not a sin. Hence physicians, in healing illnesses and administering medicines, consider the motions of the higher bodies. Those who do not do this either are ignorant of the motions of the celestial bodies or are to be judged apothecaries, not physicians.
To observe a time, however, in matters subject to free choice is a sin. Hence the Gloss on the Apostle’s words in Galatians 4, “You observe days and months and seasons and years,” blames those who follow constellations, saying: “I shall conduct business this month because this star governs the month. I shall not plant a vineyard this year because it is a leap year.”
These things are from the authors cited.