Does Matthew 5:38–42 mean that if someone attacks me or takes my belongings, I have to stand there and take it? Is it wrong to defend oneself from an attacker?

Matthew 5:38–42 is Jesus’s response to the notion that the “eye for an eye” law permitted personal vengeance. It did not. Rather, it was directed to the judges (Exodus 21:22–25), and was simply another way of saying that the compensation for a wrong done to a person must match the damages. Jesus’s directive to “turn the other cheek” can be understood two ways: First, it can be understood as a hyperbolic way of expressing how far a person should distance himself from seeking personal vengeance (and remember, personal vengeance is very different from self defense), just as “tear it out” and “cut it off” (verses 29–30) are hyperbolic ways of expressing how far a person should distance himself from sinful behavior. Second, Jesus may be speaking of situations in which resistance would only result in further damages (compare with verses 25–26). In any case, Jesus is not forbidding self-defense.