مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2559
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn ‘Abbas (رضي الله عنه) and he mentioned something. He said: The Messenger of Allah (ﷺ) used to use the siwak a great deal, to such an extent that we thought that Revelation would come down concerning it.
Musnad Ahmad 2573Hasan because of corroborating evidence; this is a da'eef is