“Abu ‘Abd Allah (a.s.), has said that once a slave who had contracted his freedom came to ’ Amir al-Mu’minin (a.s.), and said, ‘My master made a contract with me with the condition of several installment payments every year. I brought him all installments to pay at once and asked him to accept it and allow my freedom but he refused. Amir al-Mu’minin summoned him and he said, ‘He has spoken the truth.’ He (the Imam) asked, ‘Why do you not accept the assets and approve his freedom?’ He replied, ‘I accept only in installments as the condition requires and I avoid his legacy.’ Amir al-Mu’minin then said, ‘You have the right to stay with your condition.’”