Psalm 18 is the 18th psalm of the Book of Psalms, beginning in English in the King James Version: "I love you, O LORD, my strength". In the slightly different numbering of the Greek Septuagint and the Latin Vulgate, this psalm is Psalm 17. In Latin, it is also known by its incipit as "Diligam te Domine fortitudo mea". It is almost identical to 2 Samuel 22, although verse 1 of the psalm, I love you, O LORD, my strength, is not included in the Samuel version. With 50 verses, this is the longest psalm in Book 1 of the Book of Psalms (Psalms 1-41).
The psalm forms a regular part of Jewish, Catholic, Lutheran, Anglican and other Protestant liturgies. It was set to music by composers such as Heinrich Schütz.
The Jerusalem Bible describes this psalm as "a triumphal ode combining a thanksgiving prayer ... with a royal victory song, ending on a messianic note".
According to Charles and Emilie Briggs in the International Critical Commentary series, this psalm borrowed material from 2 Samuel 22, which may have been written by David himself, with later additions by multiple editors adapting it for use in public worship.
This psalm is one of a number of psalms which refer to God as a "rock" and a "fortress".
Details in the Psalm, including the language of a watery descent to Sheol, closely match details from the Book of Jonah.
The following table shows the Hebrew text of the Psalm with vowels, alongside the Koine Greek text in the Septuagint and the English translation from the King James Version. Note that the meaning can slightly differ between these versions, as the Septuagint and the Masoretic Text come from different textual traditions. In the Septuagint, this psalm is numbered Psalm 17.
Some verses of Psalm 18 are referenced in the New Testament:
In the Church of England's Book of Common Prayer, Psalm 18 is appointed to be read on the evening of the third day of the month.
The first line of Psalm 18 was paraphrased in the German hymn "Ich will dich lieben, meine Stärke" by Angelus Silesius in 1657. Heinrich Schütz set a metred paraphrase of Psalm 18 in German, "Ich lieb dich, Herr, von Herzen sehr", SWV 114, as part of the Becker Psalter.
The American composer Steve Reich set part of the Hebrew text in his 1981 work Tehillim.