The psalmist returns to the initial act of salvation in Egypt (see verses 11-12). Here again “forgot” (Good News Translation) is a deliberate act of disregarding (see verse 11). In verse 42a his power translates “his hand.” The translation of the nominal phrase his power in They did not keep in mind his power must often be translated by a verb phrase; for example, “they forgot how powerful he was.” Signs in verse 43a means “mighty acts,” and miracles translates a word rarely used (see 71.7, where Revised Standard Version translates it “a portent”). Redeemed in verse 42b is the verb used in 25.22. The reference here is to the plagues (verses 44-51).
For fields of Zoan see verse 12b. A translation should avoid suggesting, as does the Revised Standard Version literal translation, that Egypt and the fields of Zoan are two different places where God performed his miracles.
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 .