Shema-Ahavah Rabbah-Ahavat Olam-Bet Yosef
The 13th of Nisan is the Yahrtzeit of Rav Yosef Karo, Beis Yosef, Shulchan Aruch, Kesef Mishneh,and Magid Meisharim, (1488-1575). His first major work, the Beis Yosef is a comprehensive commentary on the Tur; it took 20 years to write. In it, he gathered the opinions and decisions of all the major authorities up until his time and cross-referenced them. He ruled between differing views on the basis of a consensus between the three preeminent halachic authorities, the Rif, the Rambam, and the Rosh. The work was completed in 1542, but he continued to refine it for the next 12 years, and published a second edition. After he had completed the Beis Yosef, Rav Caro made a summary of his rulings in the form of an index without reference to sources and titled it Shulchan Aruch (“Laid Table”). It was completed in 1555 in Israel; it was first published in Venice in 1565. Eventually, the Rama’s gloss (called HaMapa — “The Tablecloth”) was published together with the Shulchan Aruch in Cracow in 1578, and together they became the universally recognized Code of Jewish Law. The Rambam had published his Mishna Torah without references for his rulings. The Maggid Mishna, a commentary on Mishneh Torah written by Rabbi Vidal di Tolouse, had referenced six of the fourteen sections of the work, and Rav Caro set out to complete the references, while at the same time explaining the Rambam’s view and defending it from the Raavad. The Kesef Mishneh, as it was called, was published in Venice between the years 1574-76. Some of Rav Karo’s sheilos u’teshuvos can be found in the sefer Avkat Rokhel.
http://www.ascent.org.il/NewAscentOfSafed/Safat/Personalities/SafatSages/caro-works.html
Rabbi Jacob said in the name of Rabbi Oshaya, “Who forms light and creates darkness (Isaiah 45:7).” This is so that one should recall the attribute of day by night, and the attribute of night by day. Here, in the morning blessing, we see the attribute of night by day. But where do we find the attribute of day by night? Abaye said, “In the evening prayer, we say in the first blessing, ‘ Who rolls away the light before the darkness, and the darkness before the light.’”
What is the second blessing? Rabbi Yehudah said in the name of Shmuel, “With Great Love,” Ahavah Rabbah. Rabbi Elazar likewise taught his son, Rav Pedat, to say, “With Great Love.”
This is found in an earlier teaching: One does not say, “With Eternal Love,” Ahavat Olam, but, “With Great Love.” But the Rabbis said, “With Eternal Love,” as it is written, “With eternal love I have loved you, therefore I drew you to Me with affection (Jeremiah 31:3).” [Berachot 11a-b]
The 8th of Nisan is the Yahrtzeit of Rav Eliyahu Hakadosh of York, Rabbeinu Yom Tov (ben Yitzchak), and several other English Tosafists, who perished at Clifford’s Tower, during the Crusades, 1146: As a result of this dispute, it was ordained that “With Great Love” he said in the morning, and, “With Eternal Love” at night. [Tosafot]
This is the Ashkenazic custom. But the Sephardic custom is to say, “With Eternal Love” both morning and evening. [Bet Yosef, Orach Chaim 60]