'Horseback' in the Bible

So there went one on horseback to meet him, and said, Thus saith the king, Is it peace? And Jehu said, What hast thou to do with peace? turn thee behind me. And the watchman told, saying, The messenger came to them, but he cometh not again.

Then he sent out a second on horseback, which came to them, and said, Thus saith the king, Is it peace? And Jehu answered, What hast thou to do with peace? turn thee behind me.