Your observation, "9 lines...." etc, probably comes from a deep understanding and appreciation of the Shakespearean Poetic Form, i.e., Iambic Pentameter, which he uses almost exclusively. You are doubtless
just forgetful in mentioning the source of the 9 lines explication because in the Witches scene in "the Scottish Play" , Shakespeare shows his poetic skill and knowledge of esoteric lore by the lines:

Thrice to thine and thrice to mine,
And thrice again to make it nine,
Double, double, toil and trouble,
Fire burn and Cauldron bubble.

:curmudg