What is the ruling on entering into a partnership with a man whose wealth is predominantly unlawful?

It is preferable for a Muslim to choose a trustworthy Muslim partner so that the trade may be blessed, based on the hadith: "Indeed, Allah says: 'I am the third of the two partners as long as one of them does not betray his companion. But if he betrays him, I depart from between them.'" Al-Shawkani mentioned that the meaning of this is Allah's blessing and care for the wealth in the absence of betrayal.

As for the disbeliever and the wicked, their trustworthiness in financial dealings is not guaranteed, as Allah the Almighty says: "And indeed, many of the partners oppress one another, except for those who believe and do righteous deeds—and few are they." Accordingly, jurists have disliked partnership with a disbeliever, and with one who does not refrain from dealing in unlawful matters, such as one who does not avoid usury. This dislike increases with the increase of unlawful elements in the partner's wealth. Partnership with a Majusi (Zoroastrian), an idol worshiper, or anyone who worships other than Allah the Almighty is disliked.