Musar for Pirkei Avot 5:10
אַרְבַּע מִדּוֹת בָּאָדָם. הָאוֹמֵר שֶׁלִּי שֶׁלִּי וְשֶׁלְּךָ שֶׁלָּךְ, זוֹ מִדָּה בֵינוֹנִית. וְיֵשׁ אוֹמְרִים, זוֹ מִדַּת סְדוֹם. שֶׁלִּי שֶׁלְּךָ וְשֶׁלְּךָ שֶׁלִּי, עַם הָאָרֶץ. שֶׁלִּי שֶׁלְּךָ וְשֶׁלְּךָ שֶׁלָּךְ, חָסִיד. שֶׁלִּי שֶׁלִּי וְשֶׁלְּךָ שֶׁלִּי, רָשָׁע:
There are four middoth (i.e., character types) in a man: One who says: "Mine is mine and yours is yours" [I don't want to give you anything of mine, and please don't give me anything of yours.] This is a median middah. Some say: This is the middah of Sodom. [It approaches the middah of Sodom. For if one habituates himself to it, then even if his neighbor benefits (from what he gives him) and he lacks nothing, he will not want to give it to him. This was the middah of Sodom, their intent being to drive others away from them — even though their land was a rich one and they lacked for nothing.] "Mine is yours and yours is mine" — am ha'aretz (an ignoramus). [For he takes and gives equally, and this "settles the land." But he does not (have the sagacity to) know that (Proverbs 15:27): "the hater of gifts shall live." This is the general connotation of am ha'aretz, one who wants to make improvements but who lacks the wisdom to discriminate between what is and what is not an improvement.] "Mine is yours and yours is yours" — a chasid. [He benefits men with his possessions and he does not benefit from the possessions of others. He is a chasid, acting above and beyond the letter of the law.] "Mine is mine and yours is mine" — a wicked one.