1 Peter 5:8
Be vigilant - It means that we should exercise careful circumspection, as one does when he is in danger.
Your adversary the devil - Your enemy; he who is opposed to you. Satan opposes man in his best interests. He resists his efforts to do good; his purposes to return to God; his attempts to secure his own salvation. There is no more appropriate appellation that can be given to him than to say that he resists all our efforts to obey God and to secure the salvation of our own souls.