Solus Christus or In Christo solo (Latin in + ablative, sōlō Christō, meaning "in Christ alone") is one of the five solae that summarize the Protestant Reformers' basic belief that salvation is by faith in Christ alone.[1]
Through the atoning work of Jesus Christ alone, apart from individual works, and that Christ is the only mediator between God and man.[1][2] It holds that salvation cannot be obtained without Christ.[1][3]
This is in opposition to Catholic doctrine which Mary, mother of Jesus is also mediator between God and humanity (Mediatrix).[4]
As the foundation of the "solus christus" doctrine, various biblical verses can be invoked according to theologians.