2 is the duality of God.
3 is the spirit of a triune entity.
4 is Divine volition, capable of determining choice and forming a purpose, and manifesting activity.
Celestial.—The above numerals are combined in the following order:—1+2=3—the manifestation of the word, in the celestial world.
2+3=5—substance or quintescent matter, produced by the activity of the word.
3+4=7—the law of harmony—the providence of God in Nature. The celestial world is called by the Kabbalist the world of harmony, which none can occupy save the pure in spirit. Harmony is the only passport to Heaven.
Material.—The numeral 1, which represents the unity of God, is not represented in this world—we only have the following numerals:
2+3+4=9—humanity with the word unmanifested in the spirit. Yet it exists and can be made manifest through harmony of the spirit. It not being manifested debars humanity from the pleasure of enjoying the light of the celestial world. It is for this reason the Kabbalist called it the world of darkness or Hades. It is also called the world of discord. There are as many grades of discord here as there are harmonies in the world above. When man throws off the material covering of his soul, his consciousness reveals to him his moral standard and he gravitates to the sphere with which he is in accord. If harmonious he ascends, if discordant he descends.
10 is the synthesis of numbers. In the beginning before Deity manifested himself, it stood thus ①; in the consummation of creation it became reversed, thus 10.
Seth Pancoast.