Tafsiran Mazmur 139:16: Rashi

Your eyes saw my unformed body From the time that You created the world, Your eyes saw all the forms of the coming generations.

My unformed body Heb. גלמי. My splendor and the pattern of my form, before I was born and before I came into the world, Your eyes saw.

and on Your book they were all written And all the creatures of the world, like me, like them, even all of them, before they were created, were together revealed before You.

days have been formed and one of them All man’s deeds and the end of the days are revealed before You as if they were already formed, although not one of them was in existence, and not one was yet in the world. These are the wonders of God’s works and the way of His might, that future events are revealed to Him before they come. And so, Scripture says (Jer. 1:5): “When I had not yet formed you in the womb, etc.”

and on Your book, they were all written The book of the generations of man, which You showed to Adam.

days were formed without one of them Ultimately, many days were destined to be created, but not one of them was yet created. According to the masoretic text, in which לא is written, this is its explanation. And according to the readingfor it is read לו this is its explanation: days have been formed—He showed the days that were destined to be created, and for His share, He chose one of them, viz. the Sabbath day. Another explanation: This is the Day of Atonement, for forgiveness.

written lit. all of them will be written, like נכתבוּ.