Gittin 57 - Gladden Jerusalem
"Gladden Jerusalem and rejoice with her all those who love her; be elated with her, all those who mourn for her." (Isaiah) means: when Jerusalem is in the state of joy, one must rejoice, and when it is in mourning, one must mourn.
Seven sons of a certain woman were asked to worship idols by the Roman governor. They all refused and were executed. She told the last one, "Go, my sons, and tell Abraham your father, you bound a sacrifice on one altar, and I bound sacrifices on seven altars." She was a reincarnation of the mother of Abraham.