Peter continues to teach the believers about Christian living. He begins by giving a conclusion to his thoughts from the previous chapter about Christ's sufferings.
The phrase "arm yourselves" makes readers think of soldiers who get their weapons ready for battle. It also pictures "the same intention" as a weapon or perhaps as a piece of armor. Here this metaphor means that believers should be determined in their mind to suffer as Jesus did. Alternate translation: "prepare yourselves with the same thoughts that Christ had" (See: [[rc://en/ta/man/translate/figs-metaphor]])