How authentic is the Hadith of the Cloak mentioned in Sahih Muslim, which states its use for healing the sick?

This hadith (definition) was narrated by Muslim, Ahmad, and Al-Bayhaqi, and its chain of transmission is authentic. Al-Nawawi's commentary on the hadith clarifies that Ibn Umar's disapproval of fasting Rajab was due to his deeming it forbidden, and that he used to fast the entire month of Rajab and fast perpetually (except for the days of the two Eids and Ayyam al-Tashreeq), and this is a permissible view. As for his dislike of the banner, it was an act of piety, fearing to fall into the prohibition of silk. The purple saddle cushion was not forbidden because it was not made of silk. As for a jubbah lined with silk, it is permissible as long as its lining does not exceed four fingers. The prohibition of silk is specific to a garment made entirely of silk, or mostly of it. Asma's seeking blessings from the Prophet's jubbah (peace and blessings be upon him) was one of the Prophet's unique characteristics and is not permissible for others.