This description of Sarah is from Easton's Bible Dictionary
Sarah : princess, the wife and at the same time the half-sister of Abraham (Genesis 11:29; 20:12). This name was given to her at the time that it was announced to Abraham that she should be the mother of the promised child. Her story is from her marriage identified with that of the patriarch till the time of her death. Her death, at the age of one hundred and twenty-seven years (the only instance in Scripture where the age of a woman is recorded), was the occasion of Abraham's purchasing the cave of Machpelah as a family burying-place.
In the allegory of Galatians 4:22-31 she is the type of the "Jerusalem which is above." She is also mentioned as Sara in Hebrews 11 among the Old Testament worthies, who "all died in faith:
Through faith also Sara herself received strength to conceive seed, and was delivered of a child when she was past age, because she judged him faithful who had promised (Hebrews 11:11)
(Also see Abraham.)