网友推理出来的这两个也对：

He was said to possess the gift of prophecy. 

= People said that he possessed the gift of prophecy.

由于是 possess 是静态动词，在时间上可以跟 said 同时存在，所以可以不用完成体。

如果换成事件动词，则使用过去完成时：

He was said to have served at court for years. 

=People said that he had served at court for years. 

据说他曾在宫廷中任职多年。

在句意上，以下三句可以划等号。

He was said to have possessed the gift of prophecy. 

= People said that he had possessed the gift of prophecy.

= It was said that he had possessed the gift of prophecy.

外加两句，意思也基本相等，只是多了一些比较的含义：

As people said, he had possessed the gift of prophecy.

As was said, he had possessed the gift of prophecy.