Securitization enhances liquidity of debt contracts. However, its structural deficiency at origination has led to the freezing of its secondary market and failure of institutions holding the collateral. This paper builds on key cultural (i.e., Islamic) rulings to rectify flaws entrenched in securitized debt stemming from asymmetric information and agency issues. These injunctions help in the efficient underwriting of debt contracts across the globe to: (i) redeem its ‘toxicity’; (ii) guarantee liquidity; (iii) alleviate fragility of the financial system; and (iv) promote economic growth. Finally, this study promotes a rethink of the current ‘Islamic’ financial system from a narrow literalist juridical perspective to one that is grounded in financial economics.

We employ Amortizing Participation Mortgage (APM) to offer a novel ex post renegotiation method of a foreclosure. APM belongs to the family of home loan credit facilities advocated in the Dodd–Frank Wall Street Reform and Consumer Protection Act 2010. In our framework, APMs reduce the endemic agency costs of debt by improving affordability. These benefits increase the demand for real estate in bust times and reduce fragility of the financial system thereby preventing foreclosures. We evaluate APMs in a stochastic control framework and provide solutions for an optimal amortization schedule. We generalize our approach to partially amortizing and commercial mortgages which encompass balloon payments. Finally, we provide concrete numerical examples of home loan modifications. We also offer detailed sensitivity analysis to market parameters such as house price volatility and interest rates.