This article seeks to examine the relationship between faith-based investing of three religious traditions, stewardship and sustainability through comparative lenses. It contributes to the literature by linking faith-based investing and sustainability through an analysis of the similarities and differences in the religious values and investment stewardship approaches of faith-based investing. The article accordingly focuses on Catholic, Church of England and Islamic faith-based investing in the US, UK, and Malaysia as illustrative examples. The first section examines the concepts of sustainability, sustainable finance, and the values and organising principles underpinning Catholic, Church of England, and Islamic faith-based investing to highlight areas of conceptual alignment and their nexus to sustainability. The second section places faith-based investing within their respective legal and regulatory frameworks, illustrating an extensive reliance on soft law and a continuum from a primarily market-driven regulatory approach in the case of the US to greater state involvement in the form of law and regulation specifically tailored for Islamic faith-based investing in Malaysia. The following section then compares the faith-based investment stewardship approaches in these jurisdictions. The closing section reflects on the opportunities and challenges in faith-based investing as a means of advancing sustainability.