“任为主教”常见的英文表达可以是 “be appointed as a bishop” 或者 “be installed as a bishop” 。
“appoint”有“任命;委派”之意 ,“be appointed as a bishop” 即“被任命为主教” 。
“install”除了“安装”意思外,在宗教语境中有“(正式)使就职;为……举行就职仪式”的含义 ,“be installed as a bishop”表示“(被)正式就任为主教” ,强调就职仪式这一过程。