Bishops at this time,especially of major cities, would sometimes send around what we call a paschal letter, an Easter letter. In which they'd give instructions or different kinds of things to their churches.

当时的主教，特别是主要城市的主教，会发出所谓的复活节书信，信里写着给其他教会的指示,或者其他事情。

耶鲁公开课 - 新约课程节选