Sarai’s offer was in line with the custom of the day ​ — that a barren wife was obligated to provide her husband with a concubine in order to produce an heir.
(‏ پیدایش ۲۱ :‏ ۸ -‏ ۱۴ ؛‏ غَلاطیان ۴ :‏ ۲۹‏ )‏ این دوره در سال ۱۵۱۳ ق .‏