In 1Peter 3:8 Peter tells his readers to be of one mind. However, this is in the context of being of one mind with the believers’ enemies. This suggests a meaning of the believer seeking to understand the motives of those who seek to him harm. With this in mind, we shouldn’t be intimidated with the same fear that directs the thoughts and behavior of those who oppose us (1Peter 3:14b). The question arises, then, what did Peter’s readers’ enemies fear? I believe we are able to answer this question by reading the Scripture that Peter seems to refer to in his epistle.
Say ye not, A confederacy, to all them to whom this people shall say, A confederacy; neither fear ye their fear, nor be afraid. Sanctify the LORD of hosts himself; and let him be your fear, and let him be your dread. (Isaiah 8:12-13)
Notice “neither fear their fear, nor be afraid” answers to 1Peter 3:14b – “be not afraid of their terror, neither be troubled.” Moreover, Isaiah’s “Sanctify the Lord of hosts and let him be your fear” answers to Peter’s “Sanctify the Lord in your hearts…” (1Peter 3:15). If Peter refers to Isaiah 8, as I believe he does, what the believers’ persecutors feared was a confederacy or treason. Isaiah preached to a rebellious nation just before they went into captivity. Unbelieving Jews in the 1st century AD were afraid the Gospel would be viewed by Rome as treasonous. That is, preaching that the Messiah, the Son of David and King of the Jews, was setting up his Kingdom would be viewed by Rome as rebellion, and unbelieving Jews didn’t want Rome to destroy their nation and the Temple (cf. John 11:48). Therefore, they viewed the Gospel with suspicion and sought to destroy it before it destroyed them. Nevertheless, believers were not to fear that the Gospel was treason in any country. The fact is, throughout the 1st century AD Rome treated the Gospel as innocuous (John 18:38). Rome simply didn’t fear a King whose kingdom was not of Caesar’s world (John 18:33, 36-37).
Isaiah, to whom Peter refers, tells us that he (Christ) will be a Sanctuary on the one hand (for those who trust in him), but on the other hand he would be a Rock of offense and a trap for those (the leaders) in Jerusalem. Many will stumble because of the offence of the cross (Isaiah 8:14-15; cf. Romans 11:32-33; 1Corinthians 1:18, 23). Yet, success would be given to those who do good in the face of being treated wrongfully, but judgment would fall upon those seeking to save themselves by reaching out to harm the efforts of the Gospel (1Peter 3:12).
Therefore, the believer is to sanctify the Lord in his heart by letting God be his fear—letting God direct his thoughts and behavior (1Peter 3:15a; Isaiah 8:13). Unbelievers reject him in order that they may direct their own paths, according to their own wisdom. But, for us, Christ is our Wisdom and our Knowledge—i.e. WWJD. Peter tells us that we need to be ready with a testimony of our faith to give to whoever asks (1Peter 3:15b; cf. Acts 23:6; 24:15; 26:6-8). Contextually, the people asking questions would be those who accuse the believer of wrongdoing. Depending upon the severity of the trial, however, this could also include those in authority, who have the power to judge right and wrong (Matthew 10:18-20; Luke 21:14-15). In such a case the accusers of the brethren would probably be responsible for bringing them before the authorities.
Our defense should come out of a good conscience (1Peter 3:16a); that is, we trust that the Gospel is not intended to be rebellious or to undermine the authority of any nation. Moreover, our reply should come out of a spirit of meekness and respect (1Peter 3:15c). Peter goes on to say that doing so should shame our accusers. They should become embarrassed over how they’ve treated us. Of course, Peter doesn’t mean our enemies, because they are ashamed, would then cease their persecution and receive Christ as their Savior (cf. 1Peter 3:17). Rather, a change of heart is not part of Peter’s argument, although that could occur on an individual basis. Nevertheless, by and large, persecution would continue until the matter is resolved by God when he judges the affair himself (cf. 1Peter 1:7, 13; 2:12).