Hello, my dear friend.
You should study the Genitive Case
There is a rule related to well-known historical, classical and biblical names, which ends with -s.
The most common structure is noun (substantivo)
+ preposition of
+ noun (substantivo)
Shall we check the example:the children of Jesus Christ
(Literal meaning)the youngsters of Jesus Christ
(Literal meaning)the lambs of Jesus Christ
However, the use of the apostrophe ( ' ) is also allowed.Jesus' children
[Literal meaning].Jesus' youngsters
[Literal meaning].Jesus' lambs
The meaning in both cases does not change.
(2) HURFORD, James R. Grammar: A Student's Guide
. Language Arts & Disciplines. 1994.