Bhagavatapurana 4.2.3

4.2.3

etad ākhyāhi me brahman jāmātuḥ śvaśurasya ca /
vidveṣas tu yataḥ prāṇāṃs tatyaje dustyajān satī //

3. O sage, be pleased to tell me how this ill-will came about between the father-in-law and the son-in-law, in consequence of which Satī gave up her life, which cannot be easily done (which nobody is willing to throw away).