It is commendable to avoid transgression even out of shame before men; for in doing so, even not for the sake of Heaven, he will come to do so for the sake of Heaven.
Pesachim 50b
The highest form of shame is shame before God.
Orchot Tzadikim: Shaar HaBushah
One should accustom himself not to do anything which his friend would be ashamed to object to, such as intruding upon his friend’s privacy when the latter would be ashamed to ask him to leave.
Orchot Tzadikim: Shaar HaBushah
One should not lodge in his friend’s house when the latter is disturbed thereby and is ashamed to ask him to leave.
Orchot Tzadikim: Shaar HaBushah
One should be very careful not to impose on or ask any gift from someone, or borrow any of his articles or his money when he knows that the person would not be motivated by good will but is ashamed to turn him away empty-handed.
Orchot Tzadikim: Shaar HaBushah
There are some Mitzvot that people are not accustomed to performing and which, when one performs them, causes him to be ridiculed by others. One must bear this shame and perform the Mitzvot.
Orchot Tzadikim: Shaar HaBushah
It is very bad to be ashamed to admit the truth.
Orchot Tzadikim: Shaar HaBushah
One must not be ashamed to rebuke people (in the correct manner) and instruct them to mend their ways.
Orchot Tzadikim: Shaar HaBushah
If one is sitting in the presence of his teacher and he is ashamed to ask him what he does not know, great or small, this is very unseemly.
Mishlei 30:32 & Avot 2:5
One must take great care not to put anyone to shame for our Rabbis have taught: One who whitens his friend’s face (i.e. puts him to shame) in public has no share in The Next World. The whitening of the face is a subtle form of murder, the red blood leaving and the white pallor following.
Gemara Bava Metzia 58b & 59a
The pain of humiliation is more bitter than death. Therefore, they said: one should rather fling himself into a fiery furnace than humiliate someone in public. They derived this from Tamar (- see Bereishit 38:25-26).
Gemara Bava Metzia 59a
The destruction of Jerusalem resulted from the humiliation of Bar Kamtza.
Gemara Gitin 55b & 56a
One should not call his friend by a nickname, so he will not be ashamed.
Gemara Bava Metzia 58b
Our Rabbis taught: The sign of good children is the shame discernible on their faces, this shame attesting that they descend from Avraham, Yitzchak and Yaakov.
Gemara Yevamot 79a