Writes Rabbi Re'uven Margaliyos in Peninim U'Margaliyos (pg. 183):
We know the names of tens of thousands of great Rabbis who lived throughout the generations. Some of those names, however, are unique to a particular time period and are not found throughout Jewish history. For example, while the names Yitzchok and Yaakov are found beginning from the times of the Tannaim and Amoraim, until the era of the Geonim one does not find the name "Avraham". Similarly, in each generation of our history new names were added and manufactured, and they became rooted throughout the diaspora.
One name well known in scholarly circles, "Bahya", in truth is only held by two Rabbis we are aware of:
1) Rabbeinu Bahya Ibn Pakuda, author of Chovos Halevavos.
2) Rabeinu Bahya, author of the eponymously named commentary on the Torah, Shulchan Shel Arba, and Kad Hakemach.
In truth, one additional Bahya does appear in Rabbinic literature, R. Bahya bar Moshe of Saracosta, but that is the extent of our awareness of the existence of Jews by the name of Bahya.
For a while now, I have surmised that Bahya is not actually a name, but merely a nickname.
An ancient manuscript found in in the Spanish Royal Library in Madrid bears out my guess. On the title page found there of Kad Hakemach, written in kolofon?, is the line: "Written by R. Yehuda ben R. Asher, called R. Bahya.
In fact, Rabeinu Bahya's family name is also preserved for us in vatican manuscript #249, which is a copy of Shulchan Shel Arba. The title page reads:
Written by the wise one, Rabeinu Bahya bar Asher Ibn Hallawa, z"lThis is similarly found in bibligraohy "Alim", published by R. David Frankel, year 2....
We have also resolved the mystery of Rbeinu Bahya's father's name, which has been discussed for years by scholars.
