Leviticus 19:33

And if a stranger sojourn with you in your land
Ben Gersom, and others, understand this of a proselyte of righteousness, who was circumcised, and in all things conformed to the Jewish religion; but it may be interpreted of a proselyte of the gate, who was not an idolater, since he is described as one sojourning with them, and indeed of any stranger, who for a time was providentially cast among them: ye shall not vex him:
with hard and grievous words, upbraiding him with his former ignorance and idolatry, and saying unto him, as Jarchi observes, yesterday thou wast a worshipper of idols, and now thou comest to learn the law; nor distress him by any means in business, or with law suits; (See Gill on Exodus 22:21).