The Book of Psalms is canonical in Judaism (Ketuvim) and Christianity (Old Testament), with its authority confirmed by ancient manuscripts (Qumran), the New Testament, and councils (Hippo, Carthage). The Ethiopian Orthodox Tewahedo Church, however, has a broader canon that includes Psalm 151 as an integral part of the Psalter, accepted as Holy Scripture also by Orthodox, Syriac, and Armenian traditions, demonstrating the historical diversity of biblical canons.
Psalms
Chapter 23 — A Psalm of David.
The LORD is my shepherd; I shall not want.
He maketh me to lie down in green pastures: he leadeth me beside the still waters.
He restoreth my soul: he leadeth me in the paths of righteousness for his name's sake.
Yea, though I walk through the valley of the shadow of death, I will fear no evil: for thou art with me; thy rod and thy staff they comfort me.
Thou preparest a table before me in the presence of mine enemies: thou anointest my head with oil; my cup runneth over.
Surely goodness and mercy shall follow me all the days of my life: and I will dwell in the house of the LORD for ever.