I attended a synagogue recently for a Bar Mitzvah. I noted how some of the Jews rock when they pray. Why?

Dear Rabbi
I attended a synagogue recently for a Bar Mitzvah. I noted how some of the Jews rock when they pray. Why?
Vera
 
Dear Vera,
We don’t just rock – we roll! Some of the suggested reasons are as follows:
1. There is a verse in Psalms (35:10) which says, All my bones will speak referring to praising G-d through body language as it were.
2. Yet another verse states before my name he will bow (Malachi 2; 5) which is again a reference to physical movement during prayer.
3. There is a verse in Exodus (20:14) which tells that that the people trembled before G-d, which is also taken as a reference to prayer.
4. Finally, it is also a habit that evolved the fact that several people had to share the same prayer book in earlier times, and it was often the case that every time someone else had to bend down toe read the writing.