Here are 3 Bible verses about left-handed from the Old and New Testaments of the Holy Bible (King James Version), sorted from most to least relevant.
Judges 3:15 KJV
But when the children of Israel cried unto the LORD, the LORD raised them up a deliverer, Ehud the son of Gera, a Benjamite, a man lefthanded: and by him the children of Israel sent a present unto Eglon the king of Moab.
Judges 20:16 KJV
Among all this people there were seven hundred chosen men lefthanded; every one could sling stones at an hair breadth, and not miss.
1 Chronicles 12:2 KJV
They were armed with bows, and could use both the right hand and the left in hurling stones and shooting arrows out of a bow, even of Saul’s brethren of Benjamin.