Original footage … thanks to the efforts of the whole community *) it was finally possible to “decipher” what Einstein is saying:
“Now I will add a few words unprepared. [laughter] A country becomes really a soul only in consciously serving the intellectual life, and in the case of our Jewish people it was really this endeavour, which conserved the Jewish people as a whole. We would not be in existence today, as a community of people, without this continued, or discontinued … ehh … activity into learning and in thought and in literature.”
The occasion of this speech is still unknown, though.
*) Thanks to rubyslippez, ElmaFudd2 and especially RuniToconillo.