Satī concentrated all her meditation on the holy lotus feet of her husband, Lord Śiva, who is the supreme spiritual master of all the world. Thus she became completely cleansed of all taints of sin and quit her body in a blazing fire by meditation on the fiery elements.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
ततः स्वभर्तुश्चरणाम्बुजासवं जगद्गुरोश्चिन्तयती न चापरम् । ददर्श देहो हतकल्मषः सती सद्यः प्रजज्वाल समाधिजाग्निना
tataḥ svabhartuścaraṇāmbujāsavaṃ jagadgurościntayatī na cāparam | dadarśa deho hatakalmaṣaḥ satī sadyaḥ prajajvāla samādhijāgninā
SB 4.4.27