Tafsir of Surah Ya Sin: using Surah Ya Sin to remove hardness of heart

It is narrated from Imam Abu Ja'far Muhammad bin Ali (may Allah have mercy on him) that he said: "Whoever finds hardness and harshness in his heart should write 'Ya Sin. By the Qur'an' with saffron in a bowl, and then (pour water into it and) drink it."

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that he said: Banu Salimah lived on one edge of Madinah, and they intended to move near the Mosque (of the Prophet). So Allah, the Mighty and Majestic, revealed this verse: "Indeed, it is We who give life to the dead, and We record what they have sent ahead and their footprints." [Surah Ya Sin: 12] So the Messenger of Allah (peace and blessings be upon him) called them and said: "Your footprints (as you come to the mosque) are recorded." Then he (peace and blessings be upon him) recited this verse to them, so they abandoned (their intention to move).
This is a sahih and unusual hadith from the narration of Imam al-Thawri, and Imam Muslim has recorded part of this meaning from the hadith of Sayyiduna Anas (may Allah be pleased with him).