'Pricks' in the Bible

And he said, 'Who art thou, Lord?' and the Lord said, 'I am Jesus whom thou dost persecute; hard for thee at the pricks to kick;'

and we all having fallen to the earth, I heard a voice speaking unto me, and saying in the Hebrew dialect, Saul, Saul, why me dost thou persecute? hard for thee against pricks to kick!