Then God imposed His wisdom in His creation so that the Arabs would not take, in the meters of speech, except these three letters, the fa’, the ayn, and the lām, and they have three ranks in origin. They took a letter from each rank. They took the fa from the letters of the lips, the world of the angel and the testimony, and they took the ayn from the letters of the throat, the world of the unseen and the kingdom. And they took the lam from the middle, the world of isthmus and jibrut, which is one of the letters of the tongue that has expression and disposition in speech, so the sum of these letters, which they made as origins in the meters of speech, was one hundred and eighty degrees, and it is the half of the apparent astronomy, and it is the one that always has an effect in formation, and the absent half has no effect except where it appears.