Charles Ellicott Commentary Psalms 139:16

"Thine eyes did see mine unformed substance; And in thy book they were all written, [Even] the days that were ordained [for me], When as yet there was none of them." — Psalms 139:16 (ASV)

This difficult verse, rendered word for word, gives:

“My fetus (literally, rolled) saw your eyes,
And on your book all of them were written;
Days were formed, and not (or, as the Hebrew margin, to him) one in them.”

The Authorized Version’s reading, “substance yet being imperfect,” follows the Septuagint and Vulgate. Symmachus’s rendering, “shapeless thing,” also periphrastically denotes the embryo.

The Hebrew word itself—literally, rolled or wrapped—almost scientifically describes this. It is used in 2 Kings 2:8, rendered as “of a mantle,” and in Ezekiel 27:24, rendered as “bales” (Authorized Version: “clothes; ” margin: “foldings”). (2 Maccabees 7:22.)

Others interpret it as the ball of the threads of destiny, but this is not a Hebrew conception. By inserting the word members, the Authorized Version suggests a possible, but not a probable, interpretation. The Hebrew language often uses a pronoun before the word to which it refers has occurred (see Note, Psalms 68:14); and, despite the accents, we must refer all of them to “days” (Authorized Version: “in continuance”).

“Your eyes beheld my embryo,
And in your book were written
All the days, the days
Which were being formed,
When as yet there were none of them.”

But a much more satisfactory sense is obtained by adopting one slight change and following Symmachus in the last line:

“The days which are all reckoned, and not one of them is lacking.”

All the ancient versions interpret what is written in God’s book as either the days of life, or men born in the course of these days, each coming into being according to the Divine will.