When he saw that the tomb was empty, he believed that Jesus had risen from the dead. AT: "he saw these things and began to believe that Jesus had risen from the dead" (See: [[rc://en/ta/man/translate/figs-explicit]])
Here the word "they" refers to the disciples who did not understand the scripture that said Jesus would rise again. AT: "the disciples still did not understand the scripture" (See: [[rc://en/ta/man/translate/figs-explicit]])
The disciples continued to stay in Jerusalem. AT: "went back to where they were staying in Jerusalem" (See: [[rc://en/ta/man/translate/figs-explicit]])