"Create in me a clean heart, O God, and renew a right spirit within me"
(Ps. li. 10). Know thou that the heart is the source of life, and is
placed in the centre of the body as the Holy of holies, as stated in the
Book Zohar, is the central part of the world. Therefore one must have
his heart cleansed from evil and all evil thoughts, otherwise he
introduces an idol into the innermost part of the Temple, which ought to
be a dwelling-place for the Shechinah. (See 1 Cor. iii, 16, 17, and vi.
THE KABBALA, _Kitzur Sh'lh_, fol. 14, col. 2.