Psalm 151 is recognized as Deuterocanonical Scripture by the Greek Orthodox and Russian Orthodox Churches.
This Psalm is a genuine one of David, though extra,† composed when he fought in single combat with Goliath.
1 I was small among my brothers, and youngest in my father’s house. I tended my father’s sheep. 2 My hands formed a musical instrument, and my fingers tuned a lyre. 3 Who shall tell my Lord? The Lord himself, he himself hears. 4 He sent forth his angel and took me from my father’s sheep, and he anointed me with his anointing oil. 5 My brothers were handsome and tall; but the Lord didn’t take pleasure in them. 6 I went out to meet the Philistine, and he cursed me by his idols. 7 But I drew his own sword and beheaded him, and removed reproach from the children of Israel.