Seven
Seven was also a perfect number, as corresponding to the number of celestial orbits (including the sun, the moon, and the five known planets), the number of days in the quarter of the moon’s revolution, and the number of the gates of sense (so to speak), mouth, eyes, ears, and nostrils.
De Amicitia, Scipio’s Dream
Seven
The Kalendar and Compost of Shepherds (1493) cites the 7 Dolors of the Blessed Virgin Mary, the branches of the 7 Deadly Sins, the 7 petitions of the Lord’s Prayer, the 7 virtues, the 7 planets and their domination over man and time.
Bonaventura charts the correlation of the 7 petitions with the 7 gifts, beatitudes, virtues and vices (Expositio in cap. sextum evang. S. Matth) Honorius harmonizes the planets to the seven tones of the scale (De imagine). Albertus Magnus relates the 7 gifts of the spirit and the 7 words of Christ on the Cross (Commentarii in Psal. LVI).
“Wisdom hath builded her house, she hath hewn out there 7 pillars,” (Proverbs 9.1),
From the East are derived, wholly or in part, many of the most potent numbers of the magical arts, in particular, the number 7. The welter of Chaldean magic revolved largely about the propitiation of the 7 malevolent gods or phantoms. The Babylonian Pleiades, the Egyptian Hathors, became in this way the 7 devils of the Middle Ages, germane in origin to, but quite distinct from, the 7 deadly sins. It was the 7 devils, not the 7 sins, who taught Pietro d’Abano the 7 arts. To cope with the 7 demons, who were capable of working any harm from headache to impotence or death, it was deemed advisable to tie them up by 7 knots in a handkerchief, scarf, or girdle. The practice became well-nigh universal. Pliny’s Natural History takes cognizance of this belief (28.27).
The fact that Tristram (Thomas of Britain, The Romance of Tristam and Ysolt) learned the 7 arts, then 7 kinds of music, and shortly thereafter purchased 7 birds need only be attributed to the narrator’s delight in the number of seas, planets, days of the week, wise men, and so on. The same formula, which might be designated as part of the poetic diction of the time, accounts for the 7 Sleepers of Ephesus, the 7 Wise Masters, Tannhauser’s 7 years at Venusburg, St. George’s 7 years of torture.