Śrīla Śukadeva Gosvāmī continued: Thereafter, because of his advanced position in devotional life, Mahārāja Ambarīṣa, who no longer desired to live with material things, retired from active family life. He divided his property among his sons, who were equally as qualified, and he himself took the order of vānaprastha and went to the forest to concentrate his mind fully upon Lord Vāsudeva.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
अथाम्बरीषस्तनयेषु राज्यं समानशीलेषु विसृज्य धीरः । वनं विवेशात्मनि वासुदेवे मनो दधद्ध्वस्तगुणप्रवाहः
athāmbarīṣastanayeṣu rājyaṃ samānaśīleṣu visṛjya dhīraḥ | vanaṃ viveśātmani vāsudeve mano dadhaddhvastaguṇapravāhaḥ
SB 9.5.26