1 Peter 5:8 - Matthew Poole's English Annotations on the Holy Bible

Be sober: see 1 Peter 1:13, 1 Peter 4:7: q.d. Ye have to do with a mad enemy, a raging devil; ye had need yourselves be sober; not only in meats and drinks, &c., but as to the cares of this life, and whatsoever it is that is apt to intoxicate your minds, and expose you to him. Be vigilant; spiritually watchful and circumspect, careful of your salvation, and aware of Satan's snares and temptations, Matthew 24:42 Matthew 2:13; Matthew 25:41 1 Thessalonians 5:6. Because your adversary; or, that adversary of yours; he that contends with you, is plaintiff against you, Matthew 5:25 Luke 12:58. It answers to the Hebrew word Satan, Malachi 3:1. The devil; your accuser, he that maligns you, calumniates you, informs against you: he is so called, Matthew 2:1; Matthew 4:39, and elsewhere, because of his accusing God to men, Genesis 3:4,5, and men to God, Job 1:7, Job 2:2 Revelation 12:10, as well as each to other, 1 Thessalonians 8:44. As a roaring lion; i.e. strong, fierce, cruel, especially when hungry, and seeking his prey and roaring after it. Walketh about; is diligent and restless in his attempts, either by circumventing or assaulting you: see Job 1:7. Seeking whom he may devour; not lightly hurt, but swallow up and utterly destroy, by himself or his instruments.