Why must John write?

John had already received this very same command to write down the things that he’s seen (see Revelation 1:11). The repeated command is now accompanied by the word therefore, indicating the reason why John needs to begin writing. Jesus’ identity as John has seen it (Revelation 1:12–18)—so divine, so glorious, so overwhelming as to cause John to fall at his feet as though dead—forms the explanation as to why John must write.