Albert Barnes on Matthew 23:7

Greetings in the markets. Marks of particular respect shown to them in public places. Markets were places where multitudes of people were assembled together. They were pleased with particular attention among the multitude, and desired that all should show them particular respect.

Greetings. Salutations. Lk 10:4.

To be called--Rabbi, Rabbi. This word literally signifies great. It was a title given to eminent teachers of the law among the Jews; a title of honour and dignity, denoting their authority and ability to teach. They were gratified with such titles, and wished it given to themselves as denoting superiority. Every time it was given to them it implied their superiority to the persons who used it; and they were fond, therefore, of hearing it often applied to them. There were three titles in use among the Jews--Rab, Rabbi, and Rabban--denoting different degrees of learning and ability, as literary degrees do among us.