Tennessee Valley Bank v. Sewell

When a mortgagor conveys the mortgaged property, and his grantee assumes the payment of the mortgage as between the mortgagor and his grantee, the grantee becomes the principal debtor primarily liable for the debt, and the mortgagor becomes a surety with all the consequences flowing from the relationship. As between these two and the mortgagee, although he may treat them both as debtors, and may enforce the liability against either, still, after notice of the assumption, he is bound to recognize the condition of surety-ship and to respect the rights of the surety in all of his subsequent…