Depending on how the psalm is introduced in the previous verse, it may be advisable to drop the words He said at the beginning of this verse. This will be determined by what is most natural in the receptor language.

These verses describe the protection provided by Yahweh, using six different images:

(1) Rock (Hebrew selaʿ), that is, a boulder or large rock, a place where one can defend oneself (see also Psa 31.2; 42.9; 71.3).
(2) Fortress (see Psa 31.2, 3; 71.3; 91.2; 144.2), a place that cannot be conquered; it may be a natural formation such as a circle of large rocks, or it may be one built as a defense against enemy forces.
(3) Rock (Hebrew tsur, a term that frequently occurs in parallel lines with selaʿ in Hebrew poetry; here it is probably a synonym of the first word selaʿ). So it is acceptable to translate it by the same word in the receptor language.
(4) Shield, a protective device used in warfare to ward off enemy arrows and spears,
(5) The horn of my salvation, a figurative expression for strength and power, used of God only here and in Psa 18.2 (but see also Luke 1.69), probably owing its meaning to the horns of a bull (New Jewish Publication Society’s Tanakh translates “my mighty champion”); of my salvation can be rendered by a verbal expression, “that saves me.”
(6) Stronghold, a place of safety, either natural (like a cave) or man-made; this is very similar in meaning to the second item, fortress; in some languages it will be possible to distinguish them only by considering the first man-made and the second natural.

It is possible to consider and my deliverer as the second line and The LORD is my rock, and my fortress as the first line. In this case my deliverer makes specific what is called my rock and my fortress in the first line. The set of parallel lines in verse 3 repeats essentially the same thought, in that there is only a piling up of “strength” images. Good News Translation has not managed to keep my deliverer and has therefore lost part of the parallelism. The repetitious nature of the parallelism is reflected in Good News Translation, which uses two images, “fortress” and “shield,” and reduces the others to “protector,” “protection,” “safe,” “protects,” and “defends.”

There are also two elements in these verses that are not figurative: my deliverer and I take refuge. These may be translated “the one who delivers me” and “I hide” or “I escape.”

Good News Translation uses figurative and nonfigurative language: metaphor (“strong fortress”), simile (“like a shield”), abstract noun (“my protection”), descriptive title (“my protector”), and verbal phrases (“defends me and keeps me safe”). Variety of expression and clarity of meaning, in poetic form, should be the aim.

In these two verses there are five alternatives from which the translator must choose: (a) to keep the literal translation of the Hebrew (if and only if the meanings are clear and the figures natural); (b) to substitute other known figures from the receptor language; (c) to keep the figure, but modified to a simile, explaining its meaning through the introduction of a verb; (d) to replace the figures with nonfigurative expressions; or finally (e) to combine two or more of the foregoing. Some examples are “The LORD protects me like a rock and a fortress,” or “The LORD guards me as a rock or fortress protects people,” or “My God, you are like a rock that defends me,” or “You defend me like a shield.”

Horn of my salvation denoted the place where a person could obtain asylum or protection from enemies (Exo 21.13-14; 1 Kgs 1.50-51; 2.28). Translators may recall that Luke 1.69 also speaks of “a horn of salvation.” This expression can almost never be translated literally without providing the reader with detailed explanations. In this case it is best to follow solution (d) above, using a nonfigurative expression as in Good News Translation (“he defends me”); for example, “he saves me from my enemies” or “he keeps my enemies from harming me.” Revised English Bible speaks of “my … sure defender,” while Contemporary English Version has “my powerful weapon.”

The text of 2 Samuel here contains additional words not in Psa 18, and my refuge, my savior; thou savest me from violence. These supplementary images reinforce the ones already given. The word refuge is found in other Old Testament passages, where it is translated “way of escape” (Job 11.20) and “flight” (Amos 2.14). It carries the basic idea of retreating or fleeing in order to escape danger.

The Hebrew noun rendered violence has a wide range of meanings, and the context frequently helps determine the translation. The general meaning is violence against human life. This same noun occurs in verse 49 in the expression “men of violence,” which is parallel to “my enemies” and “my adversaries.”

Quoted with permission from Omanson, Roger L. and Ellington, John E. A Handbook on the First and Second Books of Samuel, Volume 2. (UBS Helps for Translators). New York: UBS, 2001. For this and other handbooks for translators see here .