This implies that he was permitting them to tell people about what they had seen after he rose from being dead. (See: [[rc://en/ta/man/jit/figs-explicit]])
"risen from among the dead." This speaks of becoming alive again. The phrase "the dead" refers to "dead people" and is a metonym for death. Alternate translation: "risen from death" (See: [[rc://en/ta/man/jit/figs-metonymy]])