While keeping strictly within the bounds of rabbinical orthodoxy, whose adepts respected him for his enormous erudition and strict piety, Menashe assiduously endeavored to widen their range of thought and render them more amenable to moderate freedom of research and a more sober outlook on life.

But his path was strewn with thorns.

When on one occasion he expounded before his pupils the conclusion, which he had reached after a profound scientific investigation, that the text of the Mishnah had in many cases been wrongly interpreted by the Gemara,[1] he was taken to task by a conference of Lithuanian rabbis and barely escaped excommunication.
[Footnote 1: The Mishnah is a code of laws edited about 200 C.E.

by Rabbi Judah ha-Nasi.

The Gemara consists largely of the comments of the talmudic authorities, who lived after that date, on the text of this code.] Having conceived a liking for mathematics, astronomy, and philosophy, Menashe decided to go to Berlin to devote himself to these studies, but on his way to the German capital, while temporarily sojourning in Koenigsberg, he was halted by his countrymen, who visited Prussia on business, and was cowed by all kinds of threats into returning home.