राजन्संस्मृत्य संस्मृत्य संवादमिममद्भुतम्। केशवार्जुनयोः पुण्यं हृष्यामि च मुहुर्मुहुः ॥

rājan sansmṛitya sansmṛitya saṁvādam imam adbhutam keśhavārjunayoḥ puṇyaṁ hṛiṣhyāmi cha muhur muhuḥ

O King, remembering, remembering this marvellous and holy dialogue between Keshava and Arjuna, I rejoice again and again.

In plain words: Sanjaya tells the king that each time he remembers this wonderful, holy conversation between Krishna (Keshava) and Arjuna, he feels joy again and again.