Exodus 22:22

אִם עַנֵּה תְעַנֶּה אֹתוֹ כִּי אִם צָעֹק יִצְעַק אֵלַי שָׁמֹעַ אֶשְׁמַע צַעֲקָתוֹ

If you afflict him in any way, causing him to cry out to Me, I will surely hear his cry…

This refers to mistreating converts. The next verse continues, “My anger will wax hot and I will kill you by the sword…” But in the Hebrew, the “you” in “if you afflict him” is in the singular form, while the “you” in “I will kill you by the sword” is in the plural! Why? The ibn Ezra explains that treating converts properly is a communal responsibility. If we turn a blind eye and allow one of our number to afflict a convert, we will all be held responsible.