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 64 — To the chief Musician, A Psalm of David.
Hear my voice, O God, in my prayer: preserve my life from fear of the enemy.
Hide me from the secret counsel of the wicked; from the insurrection of the workers of iniquity:
Who whet their tongue like a sword, and bend their bows to shoot their arrows, even bitter words:
That they may shoot in secret at the perfect: suddenly do they shoot at him, and fear not.
They encourage themselves in an evil matter: they commune of laying snares privily; they say, Who shall see them?
They search out iniquities; they accomplish a diligent search: both the inward thought of every one of them, and the heart, is deep.
But God shall shoot at them with an arrow; suddenly shall they be wounded.
So they shall make their own tongue to fall upon themselves: all that see them shall flee away.
And all men shall fear, and shall declare the work of God; for they shall wisely consider of his doing.
The righteous shall be glad in the LORD, and shall trust in him; and all the upright in heart shall glory.