Hello,
I have found more time to read through the story and came across what I suspect is your family tree on Ancestry. I love a good mystery ... with the added spice of the quack Dr. Brodum.
The Hebrew letter ה (ha) before Cohen (or Levi) means 'the', i.e. the Cohen (הכוהן) or the Levite (הלוי).
Turning to Copenhagen, you will find this database of the main Jewish cemetery in Copenhagen very interesting
http://tom.brondsted.dk/mosaiskebegravelser/ and the original book which formed the basis of the database
https://slaegtsbibliotek.dk/920803.pdf.
Amongst Danish Jews, men with the Hebrew name
Yehuda were generally know by the Yiddish name Leib/Lejb (pronounced 'libe'), which was secularised to Levin. I have come across very incidences of the use of the name Juda. Men with the Hebrew name
Yissachar were known by the Yiddish name
Ber, which was secularised to Berend/Berendt/Behrend, etc.
This apparent confusion with the use of two names stems from a 12th rabbinical decree that all Jewish boys had to have a Hebrew name and a Yiddish name. There are many legally (Jewish law) defined pairs, such as those cited above.
In the search for Jacob's father, this burial of Lejb Cohen of Lissa (now called Leczno in Poland) on 3 March 1789 caught my eye.
http://tom.brondsted.dk/mosaiskebegravelser/?details&id=683&kgrd=1This chap would be the perfect candidate if it were not for the fact the Ashkenazi Jews do not generally name their children after living individuals. Jacob's son Judah, who was clearly named after his grandfather, was apparently born in 1782.
Because Yissachar and Ber are an authorised pair, it would be unusual to find an individual called Yissachar son of Ber, as was supposedly the case with the good Dr. Brodum. Generally speaking, a boy would only receive his father's given name if the father had died before the boy was born.
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