This article retrieves the voices of a group of incarcerated men speaking on their religious identity and the behavioural changes ensuing from their religious choices. Research data were collected over a 10-month period from participants that consisted of a group of 30 male offenders serving life or long-term sentences at the Correctional Centre A, Zonderwater Management Area in Cullinan near Pretoria, South Africa. Qualitative research by means of an interview schedule invited offenders to share their thoughts on how their religious beliefs and experiences served as a support system during incarceration. Insight was gained into how religious identities were established to maintain a sense of belonging and hope during this period. The study embraces the Social Identity Theory that departs from the premise that individuals have multiple identities associated with the environment they live and operate in. Interpretative phenomenological analysis was used to understand the shaping of religious identity within the four themes that were identified: conserving identities; accommodating identities; contra-identities; and change of behaviour, attitudes and values. Research on religious identities operationalising into behavioural change provides knowledge to disciplines such as psychology, sociology and theology, and assists the correctional services in understanding the complex and dynamic nature of offenders when they voice themselves outside of their crimes.