Song of Songs was written by the wisest of all men – Shelomo Hamelech/ King Solomon.

“All the healing in the world are alluded to and included in the book of Shir Hashirim – the Song of Songs”. Therefore, a person in need of healing or salvation of any kind can be endowed with the blessing of salvation and mercy by reciting the Song of Songs.” If the patient is not able to say it himself his family members or his friends may say it for him. As is explained in the book
“Maam Loez” (Song of Songs, at the end of the opening), And in the book “devarim niflaim ” – “Wonderful Things” (page 117).

Some say that the most propice time for reciting this is before the morning light. Thus is explained in the book yeshuat yaakov –
“Jacob’s salvation”.
A person who makes sure to read the scroll “Shir hashirim” Song of songs” are pleasant and sung every Friday evening – erev Shabbat- he is guaranteed to be forgiven for all wrongdoings

shir hashirim was written by Shelomo hamelech. rav nachman me breslev explains the power of its healing in sihot haran 243