A man must not consider that he is called to preach until he has proved that he can speak. God certainly has not created behemoth to fly; and should leviathan have a strong desire to ascend with the lark, it would evidently be an unwise aspiration, since he is not furnished with wings. If a man be called to preach, he will be endowed with a degree of speaking ability, which he will cultivate and increase. If the gift of utterance be not there in a measure at the first, it is not likely that it will ever be developed.