John Gill Commentary Mark 12:38

"And in his teaching he said, Beware of the scribes, who desire to walk in long robes, and [to have] salutations in the marketplaces," — Mark 12:38 (ASV)

And he said unto them in his doctrine
As he was preaching, not to the Scribes and Pharisees but to the multitude, and to his disciples particularly; and to them in the audience of the people, as appears from (Matthew 23:1) (Luke 20:45) .

Beware of the Scribes ;
for though he had just spoken favourably of one of them, this was but a single man, and a singular instance; the body of that set of men, were very bad in their principles and practices, and therefore to be avoided, and that for the reasons following:

which love to go in long clothing ;
the Persic version renders it, "who affect to walk in coats and garments conspicuous, and in long robes"; such as were very particular, and different from others, and out of the common way of apparel; and so were observable and taken notice of by others: very likely it may have reference to the common length of their fringes on the borders of their outward garment, which they enlarged beyond others; (See Gill on Matthew 23:5);

and [love] salutations the market places ;
or "streets", as the Syriac and Arabic versions render it, in any public places, where there was a resort of men, and they were taken notice with respect, in a public manner. The Syriac Persic supply the word "love", as we do from (Matthew 23:6Matthew 23:7) , (See Gill on Matthew 23:6), (See Gill on Matthew 23:7).