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 151 — Psalm 151 (Ethiopian Canon - Non-Canonical in Protestant/Catholic Bibles)
I was small among my brothers, and youngest in my father's house. I tended my father's sheep.
My hands formed a musical instrument, and my fingers tuned a lyre.
Who shall tell my Lord? The Lord himself, he himself hears.
He sent forth his angel and took me from my father's sheep, and he anointed me with his anointing oil.
My brothers were handsome and tall; but the Lord didn't take pleasure in them.
I went out to meet the Philistine, and he cursed me by his idols.
But I drew his own sword and beheaded him, and removed reproach from the children of Israel.