Verses 4-6 are the answer to the question in verse 2.

Hands and heart stand for deeds and thoughts, external actions and internal motivations. Clean hands in some languages will have no reference to proper behavior, and in most languages will require recasting, as in Good News Translation “pure in act,” which may be expressed as “those who do right” or “those who have good thoughts.” However, if a figure is available, it should be used.

Line b in the Hebrew text followed by Revised Standard Version and Good News Translation is “who does not lift up his nefesh to a lie” (for nefesh see comment at 3.2, and for “lie” see comment at 12.2). Here (as in 31.6; Jonah 2.8) the word “lie” probably refers to “idols” (Good News Translation, New International Version, Biblia Dios Habla Hoy; so Dahood and others). Some, however, take the line to mean “who does not love (or, practice) lies” (see An American Translation, New English Bible); Weiser has “who does not direct his thoughts to wrongdoing.”

It should be noted that most translators follow the text of many Hebrew manuscripts and ancient versions, “his nefesh”; but the Masoretic text has “my nefesh,” which is explained as a synonym for “my (that is, Yahweh’s) name,” and the sense of the line is “who does not use the LORD’s name for false purposes” (see Exo 20.7). In the Masoretic text the ketiv is “his nefesh”; the qere is “my nefesh.” Hebrew Old Testament Text Project does not consider this passage. So New Jerusalem Bible translates “who has not taken a false oath by My life”; similarly Traduction œcuménique de la Bible “who does not use God for an evil purpose.”

If the translator follows the idea of worshiping idols, it may be possible to say, for example, “who do not worship images of God” or “who do not pray to likenesses of God.” Idols may sometimes be called “gods made of wood” or “stone gods.”

In the third line swear deceitfully is generally taken to mean “to make false promises” or “to bear false testimony under oath”; it can, however, as a parallel to the preceding line, mean “or use the name of an idol in making a promise” (see Dahood).

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 .