Mar son of Ravina


Mar son of Ravina was a Babylonian rabbi who lived around the late third century. He was not the son of Ravina I or Ravina II, but of a different Ravina.

Practices

The Talmud mentions his many unique pious practices. His friend Rav Nachman bar Yitzchak described him as "fearing Heaven" due to his strict practice of the details of halacha and his aspiration to act in a way that would full all halachic opinions. A number of his practices have become accepted halacha to this day.
An example is the situation in which one possesses a full loaf of barley bread and a slice of wheat bread, and wants to know which bread to make the Hamotzi blessing over. His approach was to place the slice within the full loaf, and make the blessing over both together.
Another example is the question of whether to put the right or left shoe on first. He would put the right shoe on without tying it, then the left shoe, then tie the left shoe, then tie the right shoe. This practice was accepted by the Shulchan Aruch.
The Talmud records a special prayer which he would say at the end of the Amidah prayer. A variation of this prayer is said by all Jews today, known by its opening words Elokai netzor.
He would let down the tefillin straps on his front side, as is done to this day. He would insert the four tzitzit strings into the corner of his garment and fold them over, forming eight strings, as is done today.
He would fast every day of the year except Purim, Shavuot, and Erev Yom Kippur - three days on which there is a special mitzvah to eat.
At his son's wedding, he considered the guests' celebration to be excessive, so he brought a cup worth 400 zuz and broke it before them, to cause him distress. This is the source of the current custom to break a cup at Jewish weddings while reciting, in memory of the destroyed Temple in Jerusalem.
He did not permit his son to perform medical bloodletting on him, considering it a possible violation of the Biblical prohibition on a son striking or wounding his parent.
Once he passed the city Babylon, which was already ruined at the time. He took some of its dust and threw it outside the city, to fulfill the Biblical prophecy "I shall sweep it with the broom of destruction".