The mortification of indwelling sin remaining in our mortal bodies, that it may not have life and power to bring forth the works or deeds of the flesh is the constant duty of believers.
John OwenI have known some good men who have been so addicted to their study, that they have thought the last day of the week sufficient to prepare for their ministry, though they employ all the rest of the week in other studies. But your business is to trade with your spiritual abilities. ... A man may preach a very good sermon, who is otherwise himself; but he will never make a good minister of Jesus Christ, whose mind and heart are not always in the work. Spiritual gifts will require continual ruminating on the things of the Gospel in our minds.
John OwenIt being our duty to mortify... we must be at work. He that is appointed to kill an enemy, if he leave striking before the other ceases living, does but half his work.
John OwenWhen sin lets us alone we may let sin alone; but as sin is never less quiet than when it seems to be most quiet, and its waters are for the most part deep when they are still, so ought our contrivances against it to be vigorous at all times and in all conditions, even where there is least suspicion.
John Owen