The saying of Allah, Exalted be His praise: "Do not consume one another's wealth unjustly among yourselves, except that it be trade by mutual consent among you." [Surah al-Nisa: 29]
And He said: "And Allah has made trade lawful and has forbidden usury (riba)." [Surah al-Baqarah: 275]
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / Q10394
Mujahid (may Allah have mercy on him) says concerning the saying of Allah Almighty: "Eat of the good things with which We have provided you" [Surah al-Baqarah: 57], that what is meant is trade.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10394
Mujahid (may Allah have mercy on him) says concerning this verse, "O you who believe, spend of the good things you have earned" [Surah al-Baqarah: 267]: O you who believe, spend from the pure provision you earn; what is meant is trade.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10395
It is narrated from Qatadah (may Allah have mercy on him) concerning the saying of Allah Almighty, "O you who believe, do not consume one another's wealth unjustly among yourselves, except by trading with one another by mutual consent" [Surah al-Nisa: 29], that he said: What is meant by it is trade; it is provision from Allah and among the things Allah has made lawful, for the one who seeks it with truthfulness and righteousness.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10396
Jumay' bin Umayr narrates from his maternal uncle Abu Burdah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) was asked which earning is the purest, or he asked: the best? He said: "A man's work with his own hand, and a sale conducted with honest intent."
Sharik bin Abdullah al-Qadi narrated it this way and erred in it in two places: one is his saying "Jumay' bin Umayr", whereas it is only Sa'id bin Umayr; and the other is in connecting its chain, whereas others narrated it from Wa'il as mursal.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10397
Sa'id bin Umayr, whose maternal grandfather was Sayyiduna al-Bara' bin Azib (may Allah be pleased with him), narrates that the Prophet (peace and blessings be upon him) was asked: "Which of a man's earnings is the purest?" He (peace and blessings be upon him) said: "A man's work with his own hand, and every lawful sale."
This is the preserved version, as mursal.
(b) Sa'id narrates from his paternal uncle that the Messenger of Allah (peace and blessings be upon him) was asked: "Which earning is the best?" He said: "A pure earning."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10398
Sa'id bin Umayr narrates the same hadith from his paternal uncle.
Others narrated it from Sufyan as mursal. Sharik said: from Wa'il bin Dawud, from Jumay' bin Umayr, from his maternal uncle Abu Burdah; and "Jumay'" is a mistake. Al-Mas'udi said: from Wa'il bin Dawud, from Abayah bin Rafi' bin Khadij, from his father; and that is a mistake. The correct version is the narration of Wa'il from Sa'id bin Umayr from the Prophet (peace and blessings be upon him) as mursal. Al-Bukhari said: Some of them narrated it with a connected chain, and that is a mistake.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 10399