New Defender's Study Bible Notes
3:16 book of remembrance. In heaven God keeps records of not just the actions of His people but even of their thoughts! This verse indicates His particular pleasure when His people truly fear the Lord and He occupies both their conversations and their inward thoughts, even (perhaps especially) when most of their contemporaries ignore or reject Him.
3:17 my jewels. The word translated “jewels” only this once is translated “peculiar treasure” three other times. The connotation is that of no ordinary jewels, but of certain very special treasures. To God, those who fear Him, and think on His name, and often speak to one another about Him, are very special people, as dear to Him as a faithful only son of a loving father.