Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 20
श्रीराजोवाचकथं रुक्म्यरीपुत्राय प्रादाद् दुहितरं युधि ।कृष्णेन परिभूतस्तं हन्तुं रन्ध्रं प्रतीक्षते ।एतदाख्याहि मे विद्वन् द्विषोर्वैवाहिकं मिथ: ॥ २० ॥
śrī-rājovācakathaṁ rukmy arī-putrāyaprādād duhitaraṁ yudhikṛṣṇena paribhūtas taṁhantuṁ randhraṁ pratīkṣateetad ākhyāhi me vidvandviṣor vaivāhikaṁ mithaḥ
King Parīkṣit said: How could Rukmī give his daughter to his enemy’s son? After all, Rukmī had been defeated by Lord Kṛṣṇa in battle and was waiting for an opportunity to kill Him. Please explain this to me, O learned one — how these two inimical parties became united through marriage.