Adam Clarke Bible Commentary

Seven days - The priest in his consecration was to abide seven days and nights at the door of the tabernacle, keeping the Lord's watch. See Lev 8:33, etc. The number seven is what is called among the Hebrews a number of perfection; and it is often used to denote the completion, accomplishment, fullness, or perfection of a thing, as this period contained the whole course of that time in which God created the world, and appointed the day of rest. As this act of consecration lasted seven days, it signified a perfect consecration: and intimated to the priest that his whole body and soul, his time and talents, should be devoted to the service of God and his people. The number seven, which was a sacred number among the Hebrews, was conveyed from them down to the Greeks by means of the Egyptian philosophy, from which they borrowed most of their mysteries; and it is most likely that the opinion which the Greeks give is the same that the original framers of the idea had. That there was some mystical idea attached to it, is evident from its being made the number of perfection among the Hebrews. Philo and Josephus say that the Essenes, an ancient sect of the Jews, held it sacred "because it results from the side of a square added to those of a triangle." But what meaning does this convey? A triangle, or triad, according to the Pythagoreans, who borrowed their systems from the Egyptians, who borrowed from the Jews, was the emblem of wisdom, as consisting of beginning (Monad), middle (Duad), and end (Triad itself); so wisdom consists of three parts - experience of the past, attention to the present, and judgment of the future. It is also the most penetrating of all forms, as being the shape of the wedge; and indestructibility is essential to it, as a triangle can never be destroyed. From those three properties it was the emblem of spirit. The square, solid, and tetrad, by the same system were interchangeable signs. Now a square is the representation of a solid or matter, and thus the number seven contains within itself the properties of both the triangle or solid, and the square or tetrad, i.e., is all emblem of body and spirit; comprehends both the intellectual and natural world; embraces the idea of God, the chief of spirits or essences; and all nature, the result of his power; thus a very fit emblem of perfection. It is perhaps in this way that we must explain what Cicero, Tusc. Quest., lib. i., cap. 10, says of the number seven, where he calls it the knot and cement of all things; as being that by which the natural and spiritual world are comprehended in one idea. Thus the ancient philosophers spoke of numbers, themselves being the best judges of their own meaning.