It is narrated from Sayyiduna Jabir (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "Remorse (regret) is repentance."
No one narrated this hadith from Ibn Jurayj except Abu Asim, and al-Qasim bin Muhammad bin Abbad is alone in narrating it from him.
Hadith Referenceالمعجم الأوسط / باب الميم / 7350
Hadith Takhrij«أخرجه الطبراني فى «الأوسط» برقم: 101»