Rejoice of course in souls saved; rejoice in successes of the gospel, but don’t rejoice in the authority and power given to you personally, and that the powers of darkness are subject to you, says the Lord Jesus. That might seem something so extraordinary as to carry you away with wonder – that demons, who are so much more powerful than you are, have, at your word, been made to cease their torment of a human soul, because of a gift that your Lord has given you – but that is not your biggest cause of rejoicing.