Devibhagavatapurana 2.5.41

2.5.41

pitrājñayā jāmadagnyena pūrvaṃ chinnaṃ śiro māturiti prasiddham |
akāryamapyācaritaṃ ca tena guroranujñā ca garīyasī kṛtā ||

It is well known that, in ancient days, the Jamadagni's son Paras'urâm cut off his mother's head under the orders of his father. He considered the father's words more important, and hence could do such an unjust act. O king! This my body is at your disposal; I can certainly do what you order me to do. So say what am I to do? as long as I am living, you need not express any sorrow; if you permit, I will do what is even hardly practicable to do. O king! Say why you are anxious; I will remove that at once with this bow in my hand. If my body goes in carrying your mandate know that your desire will be fructified. Fie to that son, who, being capable, is averse to do what his father desires! What use is there in having a son who does not remove the cause of his father's anxiety? Hearing the words of the son, the king S’antanu felt much ashamed in his heart and said:-- “O son! This is now my gravest care that you are my only son; besides you are a hero very powerful, honoured and never showing your back in battles; therefore, if, out of ill-luck you become dead in some battlefield, I will become issueless; under such circumstances what am I to do? So, O son! My life is fruitless when I have got only one son; this is my gravest care; therefore I am sorry. O son! I have no other cares that I can mention to you.” Hearing these words of the father, Gângeya called the old ministers and said that the king was too ashamed to speak out to me the real matter; so I ask you all to know exactly the king's cares and communicate them to me as they are; I can carry them out, without any hitch, then. At these Bhîsma's words, the ministers went to the king, and learned the true cause, and spoke to Bhîsma; learning this, he began to think what ought to be done.
The Gangâ's son Bhîsma, then, accompanied by the ministers, quickly went to the house of the fisherman, and with words of humility and affection, spoke:-- “O tormentor of foes! I pray to you to give your beautiful daughter in marriage to my father. Your daughter will
be my mother and I will be her servant.” The fisherman, then, said:-- “O highly lucky prince! Then the king's son will not be able to become king, in your presence; so kindly marry yourself my daughter.” At this Bhisma again said:-- Let your daughter be my mother; I will never accept the kingdom. The son of your daughter will, no doubt, become king. The fisherman said:-- “I know your words are true; but if your son be powerful, he can take forcibly the kingdom for himself.” At this Bhîsma again said:-- “O Sire! Know my words as true; I will never marry; from to-day I have accepted this difficult vow.” Sûta said:-- Hearing this firm resolve of Bhîsma; the fisherman gave over his beautiful daughter to the king S’antanu. Thus S’antanu married the dear Satyavatî; but he was quite unaware of the wonderful birth of Vyâsa Deva.
Thus ends the fifth Chapter of the second Skandha on the marriage of Satyavatî in the Mahâpurâna S’rîmad Devî Bhâgavatam of 18,000 verses.