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 54 — To the chief Musician on Neginoth, Maschil, A Psalm of David, when the Ziphims came and said to Saul, Doth not David hide himself with us?
Save me, O God, by thy name, and judge me by thy strength.
Hear my prayer, O God; give ear to the words of my mouth.
For strangers are risen up against me, and oppressors seek after my soul: they have not set God before them. Selah.
Behold, God is mine helper: the Lord is with them that uphold my soul.
He shall reward evil unto mine enemies: cut them off in thy truth.
I will freely sacrifice unto thee: I will praise thy name, O LORD; for it is good.
For he hath delivered me out of all trouble: and mine eye hath seen his desire upon mine enemies.