In the Holy Book of Psalm 53 and 14 are exactly the same. Why is that psalm listed twice in the Holy Bible?
There is a remarkable resemblance between Psalm 56 and Psalm 14, but they are not exactly the same. The difference in the two compositions is (a) in the title, and (b) in the psalm itself.
(a) In the title. Both psalms are ascribed to David, and both are dedicated to the "Chief Musician." But in the title to Psalm 53, there is this addition: "Set to Mahalath" It is supposed to denote a stringed instrument, as a lute or guitar that was designed to be accompanied with the voice.
(b)Verse 6 of Psalm 14 and all the illustrations revealing the writer’s stream of thought following the verse are omitted from Psalm 53. It could be that the author of the psalm-- David—might have revised it himself, and made these changes to express his idea more elaborately while retaining the original psalm in the collection to be used during the service of God. Similar changes are found in (Ps 18), as compared with (2 Sam 22), which give the psalm in its original form of composition.