In parallel with verse 17, it seems that My foot slips in verse 18a means imminent death and not simply danger (see 18.36b; 38.16b-17a). Verse 18 begins literally “When I said.” In the context it seems that “shouted” or “called out” would be more appropriate, but most translations keep it as in Good News Translation. Revised Standard Version has chosen I thought (New Jerusalem Bible “I think”), which is suitable. New English Bible is good, “When I felt that my foot was slipping.”

In verse 19 Good News Translation “I am anxious and worried” translates “the many thoughts in my heart.” The Hebrew word for “thoughts” is found only here and in 139.23; here the thoughts are clearly disquieting and worrisome. In verse 19b thy consolations is best represented by a verb phrase, “you console (or comfort, or reassure)”; and “my nefesh” (my soul) is again a way of saying “me.”

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 .