1. Muhammad ibn Yahya has narrated from Muhammad ibn al-Husayn from Safwan from al-‘Ala’ from Muhammad ibn Muslim who has said the following: “Upon my asking one of the two Imam, (abu Ja’far or abu ‘Abd Allah), ‘Alayhim al-Salam, about the case of a man who forms a contract for a certain work with another man but he does not do the work, instead he gives it to someone else and makes a certain amount of profit. He (the Imam) said, ‘No, he cannot do so unless he does certain work in it.’”