Greetings in the markets - Markets were places where multitudes of people were assembled together. They were pleased with special attention in public places, and desired that all should show them particular respect.
Greetings - Salutations. See the notes at Luke 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 honor and dignity, denoting 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.

To be called of men, Rabbi, Rabbi - רבי רבי, i.e. My teacher! my teacher! The second rabbi is omitted by several excellent MSS., by most of the ancient versions, and by some of the fathers. Griesbach has left it in the text, with the note of doubtfulness.
There are three words used among the Jews as titles of dignity, which they apply to their doctors - Rabh, Rabbi, and Rabban; each of these terms has its particular meaning: rabban implies much more than rabbi, and rabbi much more than rabh.
They may be considered as three degrees of comparison: rabh great, rabbi greater, and rabban greatest. These rabbins were looked up to as infallible oracles in religious matters, and usurped not only the place of the law, but of God himself.

And greetings in the markets, and to be called of men, Rabbi, (f) Rabbi.
(f) This word "Rabbi" signifies one that is above his fellows, and is as good as any of them: and we may see by the repeating of it how proud a title it was. Now they were called Rabbi who, by the laying on of hands, were uttered and declared to the world to be wise men.

And greetings in the markets,.... They used to stroll about the markets, being public places, where there was a great concourse of people, on purpose to be taken notice of before multitudes, with singular marks of respect; as stretching out the hand, uncovering the head, and bowing the knee:
and to be called of men Rabbi, Rabbi; because of their great authority, and largeness of their knowledge: the repetition of the word Rabbi, is not made in the Vulgate Latin, nor in the Syriac, Arabic, Persic, and Ethiopic versions, nor in Munster's Hebrew Gospel, but is in all the Greek copies, and very justly; since it was usual in the salutations of them, to double the word. It is reported (f) of R. Eleazar ben Simeon, of Migdal Gedur, that having reproached a deformed man he met in the road; when he came to the city where the man lived,
"the citizens came out to meet him, and said to him, peace be upon thee, , "Rabbi, Rabbi, Master, Master"; he (Eleazar) said to them, who do you call "Rabbi, Rabbi?" They replied to him, he who followed thee: he said unto them, if this be a Rabbi, let there not be many such in Israel.''
The Jews pretend, that king Jehoshaphat used to salute the doctors with these titles; though they forget that they were not in use in his time, as will be hereafter observed: they say (g),
"whenever he saw a disciple of the wise men, he rose from his throne, and embraced and kissed him, and called him, , "Father, Father, Rabbi, Rabbi, Master, Master".''
Where you have the three different words used by our Lord in this and the following verses, by which these men loved to be called, and he inveighed against; nay, they not only suggest, that kings gave them these honourable titles, and they expected them from them, but even they liked to be called kings themselves. It is said (h) of R. Hona arid R. Chasda, that as they were sitting together, one passed by them,
"and said to them, "peace be to you kings", "peace be to you kings": they said to him, from whence does it appear to thee, that the Rabbins are called kings? He replied to them, from what is written, "by me kings reign", &c. They said to him, from whence hast thou it, that we are to double or repeat peace, or salutation to kings? He answered them, that R. Judah said, that Rab said from hence, 1-Chronicles 12:18. "Then the spirit came upon Amasai", &c.''
This title began but to be in use in the time of our Lord, or a very little while before: none of the prophets had it, nor Ezra the Scribe, nor the men of the great synagogue, nor Simeon the Just, the last of them; nor Antigonus, a man of Socho, a disciple of his: and it is observed by the Jews themselves (i), that
"the five couple are never called by the name of Rabban, nor by the name of Rabbi, only by their own name.''
By whom are meant, Joseph ben Joezer, and Joseph ben Jochanan; Joshua ben Perachia, said to be the master of Jesus of Nazareth, and Nittai the Arbelite; Judah ben Tabai, and Simeon ben Shetach; Shemaiah and Abtalion; Hillell and Shammai. The sons, or disciples of the two last, first took these titles. Rabban Simeon, the son of Hillell, thought by some to be the same Simeon that had Christ in his arms, is (k) said to be the first that was called by this name; and it is also observed by them (l), that Rabban was a name of greater honour than Rabbi, or Rab, and that Rabbi was more honourable than Rab; and to be called by a man's own name, was more honourable than any of them. The Karaite Jews make much the same complaint, and give much the same account of the pride and vanity of the Rabbinical doctors, as Christ here does; for so one of them says (m);
"The Karaites do not use to act according to the custom of the wise men among the Rabbans, to make to themselves gods of silver, and guides of gold, with this view, , "to be called Rab"; and also to gather wealth and food to fulness, &c.''
(f) T. Bab. Taanith, fol. 20. 2. (g) T. Bab. Maccot, fol. 24. 1. & Cetubot, fol. 103. 2. (h) T. Bab. Gittin, fol. 62. 1. (i) Ganz. Tzemach David, par. 1. fol. 21. 1. (k) Ganz. Tzemach David, par. 1. fol. 25. 1. (l) lb. (m) Eliahu Adderet, c. 6. apud Trigland. de. Sect. Kar. c. 10. p. 164.

And greetings in the markets, and to be called of men, Rabbi, Rabbi--It is the spirit rather than the letter of this that must be pressed; though the violation of the letter, springing from spiritual pride, has done incalculable evil in the Church of Christ. The reiteration of the word "Rabbi" shows how it tickled the ear and fed the spiritual pride of those ecclesiastics.

And salutations in the markets. Being greeted by titles of honor in the public resorts.
To be called Rabbi. A term which meant the same as Doctor of Divinity now. There were three degrees, Rab, Rabbi, and Rabboni. The last is the greatest, and means, literally, "My great teacher."