What is the ruling if the creditor transfers the debt obligation to another party (a novation of debt)?
Chapter on Guarantee (Daman)
Al-Mughni
Book of Assignment (Transfer of Debt)
Primary text
If the creditor transfers the debt obligation (Ihalat al-ghareem) to another party, both the principal debtor and the guarantor are absolved. This is because the right is singular, and its satisfaction, even through transfer, removes the attachment to them, just as in the case of satisfying a mortgaged debt.
Supporting text
If either the principal debtor or the guarantor institutes the transfer (Halah) to the creditor, both are absolved because the novation (Halah) is considered equivalent to payment (Qada').