R. Eliezer Yehuda was a well-known contemporary halachic authority who resided in Jerusalem. His halachic decisions are held in high esteem, especially in the field of medical practice. Many of these decisions appear in his 22-volume set of responsa titled Tzitz Eliezer.
Link: Judaism and Medicine
Today is the first of the two Rosh Chodesh ("Head of the Month") days for the month of Kislev (when a month has 30 days, both the last day of the month and the first day of the following month serve as the following month's Rosh Chodesh).
Special portions are added to the daily prayers: Hallel (Psalms 113-118) is recited -- in its "partial" form -- following the Shacharit morning prayer, and the Yaaleh V'yavo prayer is added to the Amidah and to Grace After Meals; the additional Musaf prayer is said (when Rosh Chodesh is Shabbat, special additions are made to the Shabbat Musaf). Tachnun (confession of sins) and similar prayers are omitted.
Many have the custom to mark Rosh Chodesh with a festive meal and reduced work activity. The latter custom is prevalent amongst women, who have a special affinity with Rosh Chodesh -- the month being the feminine aspect of the Jewish Calendar.
Links: The 29th Day; The Lunar Files
Noah was a tzadik, a very great man. He saved the entire world. But he didn't approach Abraham's greatness.
When G‑d told Noah to build an ark before the world would be destroyed, Noah built an ark.
But when G‑d told Abraham He was about to destroy the cities of Sodom and Gomorrah—cities corrupt and evil to the core—Abraham argued. He said, “Perhaps there are righteous people there! Will the Judge of All the Earth not do justice?”
Where Noah donned a warm coat for himself and his family, Abraham built a warm fire for the entire world.
Because Abraham felt a sense of ownership for the world in which he lived. If there was something wrong, it needed to be changed. Even if it had been decreed by the will of G‑d.