Tradition attributes Psalm 27 to King David. Protestant Christians have traditionally thought of it as written early in David's life, during his flight from King Saul, with Spurgeon suggesting the incident with Doeg the Edomite specifically.
Catholic doctrine has traditionally seen the Psalm in two sections. The first section declares the power of God and a boundless hope that God will bring rescue, and protection from all enemies. The second portion has a clear shift in tone  with declaration “I believe". Some scholarship contends it may have originally been two separate Psalms.
- Is recited twice daily from Rosh Chodesh Elul to Shemini Atzeret, a period of repentance based in the Midrash.
- Verse 7 is found in the repetition of the Shacharit Amidah during Rosh Hashanah.
- Verse 13 is found in the Mussaf Amidah on Rosh Hashanah.
- Verse 14 is the opening of verses recited before Ein Keloheinu.
In the Roman Rite liturgy, this Psalm is recited, divided into its two parts, at Vespers on Wednesday of the first week of the four-week cycle, as well as being used often as a responsorial psalm at Mass.
A New Catholic Commentary on Holy Scripture says the first poem of which Psalm 27 is composed is an expression of confidence that God will bring help and of devotion to the Temple, and the second is a cry for help. Mary Kathleen Glavich's The Catholic Companion to the Psalms recounts how a woman wrote the first verses of Psalm 27 (boundless hope that God will bring rescue) on the wall of the brothel room where she was confined against her will. Pope John Paul II also spoke of the first part of the psalm as "marked by a deep tranquillity, based on trust in God on the dark day of the evildoers' assault". In the second part too, he said, "the decisive element is the trust of the person of prayer in the Lord", whose face the person seeks, an expression of "the mystical need of divine intimacy through prayer", an intimacy made possible even in this life through Christ.
Matthew Henry similarly saw the Psalm as a metaphor for the Christian life, that “whatever the Christian is as to this life, he considers the favour and service of God as the one thing needful...” while Spurgeon sees the Psalm as at once the language of David, but also descriptive of the Church, and Jesus. Calvin saw it more as a prayer of thankfulness and composure.
- Artur Weiser (1 October 2000). The Psalms: A Commentary. Westminster John Knox Press. p. 251. ISBN 978-0-664-22297-0.
- Charles Augustus Briggs; Emilie Grace Briggs (1960) . A Critical and Exegetical Commentary on the Book of Psalms. International Critical Commentary. 1. Edinburgh: T & T Clark. p. 237.
- For an author who sees it as a unified whole but acknowledges the existence of scholars who hold to a composite structure, see John Phillips (October 2001). Exploring Psalms: An Expository Commentary. Kregel Academic. p. 203. ISBN 978-0-8254-3492-1.
- Psalm 27 (New International Version) at Bible Study Tools.
- psalms 27 at Bible Hub.
- Haydock's Catholic Bible Commentary, 1859 Psalm 27.
- Matthew Henry, Commentary on the Whole Bible Psalms 27.
- Charles H. Spurgeon, The Treasury of David Archived 2014-12-04 at the Wayback Machine..
- Psalm 27:4–6).
- Psalms 27:7–12.
- Rabbi Benjamin J. Segal Psalm 27 .
- Nicolaas Herman Ridderbos: Die Psalmen: Stilistische Verfahren und Aufbau mit besonderer Berücksichtigung von Psalm 1-41, (Berlin 1972), p211.
- The Complete Artscroll Siddur page 170
- The Complete Artscroll Machzor for Rosh Hashanah page 349
- The Complete Artscroll Machzor for Rosh Hashanah page 465
- The Complete Artscroll Siddur page 477
- Le cycle principal des prières liturgiques se déroule sur quatre semaines.
- Reginald C. Fuller, Leonard Johnston, Conleth Kearns (editors), A New Catholic Commentary on Holy Scripture (Nelson 1969)
- Mary Kathleen Glavich, The Catholic Companion to the Psalms (ACTA Publications 2008 ISBN 978-0-87946364-9), p. 25
- Pope John Paul II General Audience, Wednesday, 28 April 2004.
- Matthew Henry, Psalm 27.
- Calvin's Commentaries, Vol. 8: Psalms, Part I, translated . by John King, [1847-50], at sacred-texts.com.