مُسْنَدُ أَحْمَدَ
Musnad Ahmad 3021
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn Abbas, who attributed it to the Prophet (ﷺ): "Every covenant that was made during the Jahiliyyah, Islam only strengthens and reaffirms it.”
Musnad Ahmad 3045A Saheeh hadeeth; this is a da'eef isnad]