Funny it’s in the non-Catholic religions thread here:
The best source is the Bible, of course.
Also check out the Catholic Encyclopedia at New Advent (Google it). Just remember to look up Sarah as “Sara” and Hagar as “Agar” (they use the older spellings. You will find that they will give you not only the Genesis chapters but also specific verses in the NEW TESTAMENT which reference both women.
God bless!
