In verse 19a afflictions means troubles, difficulties, bad things, sufferings, misfortunes. A translation can say “Many bad things happen to good people.”

Delivers in verse 19b translates the same verb used in verse 7. The thought is not that Yahweh does not allow bad things to happen to good people, but that he does not let them be defeated or destroyed by them.

In verse 20a He refers to Yahweh and his to the righteous person. Keeps has the meaning “guards.”

The expressive language in verse 20 portrays Yahweh’s care and concern. Most translations keep the poetic language about bones, but there may be some cases in which the figures would be taken literally; in such instances a more general statement can be made, such as “The LORD protects him with great care and does not let him be hurt in the least.”

The language of verse 20b is used in John 19.36, but the source of the thought of the quotation is rather Exodus 12.46 and Numbers 9.12, passages which speak of the passover lamb.

Quoted with permission from Bratcher, Robert G. and Reyburn, William D. A Handbook on the Book of Psalms. (UBS Helps for Translators). New York: UBS, 1991. For this and other handbooks for translators see here .