Isaia 49:2

And he hath made my mouth like a sharp sword; in the shadow of his hand hath he hid me, and made me a polished shaft; in his quiver hath he hid me;

Ver. 2. And he hath made my mouth like a sharp sword.] He hath added efficacy to my doctrine, and will protect my person till I have finished the work that he gave me to do.

And made me a polished shaft.] That, being well pointed, will pierce at a distance, and either prick converts at the heart, as Act 2:37 or cut refractories to the heart. as Act 7:54 Christ will pursue his enemies both with the terrors of his words, his mouth being "made like a sharp sword," and with the plagues of his hands, being made like a polished shaft.