Jason Biggs better learn the horah ... 'cause his dog turned 13 Thursday -- and his wife threw the cute pooch its own "bark mitzvah" to celebrate.

Like a true yenta ... Jason's wife Jenny Mollen documented the whole ceremony on her Instagram when she and Biggs took the dog -- named Teets -- to a temple to make things official.

The whole fam dined on challah afterward to commemorate the special day.

It's unclear if she guilted Teets into taking these photos. But c'mon ...

Read more: http://www.tmz.com/2014/01/31/jason-biggs-wife-jenny-mollen-dog-bar-mitzvah/#ixzz2sBIMBPHK