So the chief priests made plans to kill Lazarus as well, for on account of him many of the Jews were going over to Jesus and putting their faith in him.
Its not correct to say that the «Jews» did not believe that Jesus was the Messiah. When he rose Lazarus from the dead, many Jews came to Jesus. They were men and women of faith, who gave their life to Him. The Chief priest had been rebuked by the Messiah, and plotted to kill both Him and Lazarus.