Abstract: A method for quantum-resistant digitally signing data, a method for verification of a quantum resistant digital signature for authentication of a source of data by verifying a private key, and a quantum resistant digital signature system are provided. The quantum resistant digital signature system includes a digital signature system and a layer of quantum resistant protection. The digital signature system includes a public key and a private key, wherein the public key is associated with the private key. The digital signature system also includes a digital signature generated in response to data and the private key. The layer of quantum resistant protection is applied to the digital signature system and includes a signing-party-provided quantum-secure proof of knowledge of a pre-image of the private key.