SB 3.1.12

pārthāṁs tu devo bhagavān mukundo
 gṛhītavān sakṣiti-deva-devaḥ
āste sva-puryāṁ yadu-deva-devo
 vinirjitāśeṣa-nṛdeva-devaḥ
Synonyms: 
pārthān — the sons of Pṛthā (Kuntī); tu — but; devaḥ — the Lord; bhagavān — the Personality of Godhead; mukundaḥ — Śrī Kṛṣṇa, who awards liberation; gṛhītavān — has taken up; sa — with; kṣiti-deva-devaḥ — the brāhmaṇas and the demigods; āste — is present; sva-puryām — along with His family; yadu-deva-devaḥ — worshiped by the royal order of the Yadu dynasty; vinirjita — who have been conquered; aśeṣa — unlimited; nṛdeva — kings; devaḥ — Lord.
Translation: 
Lord Kṛṣṇa, the Personality of Godhead, has accepted the sons of Pṛthā as His kinsmen, and all the kings of the world are with Lord Śrī Kṛṣṇa. He is present in His home with all His family members, the kings and princes of the Yadu dynasty, who have conquered an unlimited number of rulers, and He is their Lord.
Purport: 

Vidura gave Dhṛtarāṣṭra very good counsel regarding political alliance with the sons of Pṛthā, the Pāṇḍavas. The first thing he said was that Lord Kṛṣṇa was intimately related with them as their cousin. Because Lord Kṛṣṇa is the Supreme Personality of Godhead, He is worshipable by all brāhmaṇas and demigods, who are the controllers of the universal affairs. Besides that, Lord Kṛṣṇa and His family members, the royal order of the Yadu dynasty, were the conquerors of all kings of the world.

The kṣatriyas used to fight the kings of various dominions and kidnap their beautiful princess-daughters after conquering their relatives. This system was laudable because the kṣatriyas and the princesses would be married only on the basis of the chivalry of the conquering kṣatriya. All the young princes of the Yadu dynasty married the daughters of other kings in this way, by chivalrous force, and thus they were conquerors of all the kings of the world. Vidura wanted to impress upon his elder brother that fighting with the Pāṇḍavas was fraught with many dangers because they were supported by Lord Kṛṣṇa, who had conquered, even in His childhood, demons like Kaṁsa and Jarāsandha and demigods like Brahmā and Indra. Therefore all universal power was behind the Pāṇḍavas.