One way to understand the English word form is to consider its opposite, the formless. The formless is the dark, the shifting, the unknowable, the airy, the undistinct, etc. When Genesis describes the world before creation as “without form and void, and the Spirit of God moved upon the waters of the deep.” it draws to mind the right image of the formless as what lacks being [void] and is unknown [the waters of the deep without light]. Now since the formless first brings to mind to be dark and unintelligible, one of the original meanings of form traces back to the Greek morphe, which derives from the Indo-European root mer-bh meaning to shine or to sparkle. This sense did not transfer into the English word form, but it is a single idea that stands behind all of the meanings, and a meaning that, again, is implied in the meaning of the word “formless”
This shining or sparkling is both the splendor of existing (which gives us the sense of “to form” which means “to cause to be”) and of being intelligible (for what is known is brought to light). The word form also denotes the complete and the perfect, for what has been formed has been completed, and what has been reformed has been brought back to some original splendor or goodness.
