Mujahid, al-Hasan and al-Dahhak (may Allah have mercy on them) say regarding the saying of Allah Almighty: 'two just men from among you, or two others from outside you' [Surah al-Ma'idah: 106]: There were two Christian men from the people of Darin, one of them from Tamim and the other from Yemen. They accompanied a Qurayshi on a trading journey, and the Qurayshi's property was known.
Imam al-Shafi'i (may Allah have mercy on him) said: The meaning of 'the testimony among you' [Surah al-Ma'idah: 106] is swearing oaths among yourselves.
The meaning of what Muqatil bin Hayyan mentioned from the exegetes is established with a sahih (authentic) chain from Ibn Abbas (may Allah be pleased with them both), except that the claim of Tamim and Adi that they had bought it is not preserved in it, while Muqatil preserved it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الشهادات / 20624