SB 4.28.32
agastyah prag duhitaram
upayeme dhrta-vratam
yasyam drdhacyuto jata
idhmavahatmajo munih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The great sage named Agastya married the first-born daughter of Malayadhvaja, the avowed devotee of Lord Krsna. From her one son was born, whose name was Drdhacyuta, and from him another son was born, whose name was Idhmavaha.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The name Agastya Muni is very significant. Agastya Muni represents the mind. The word agastya indicates that the senses do not act independently, and the word muni means “mind.” The mind is the center of all the senses, and thus the senses cannot work independent of the mind. When the mind takes to the cult of bhakti, it engages in devotional service. The cult of bhakti (bhakti-lata) is the first daughter of Malayadhvaja, and as previously described, her eyes are always upon Krsna (asiteksanam). One cannot render bhakti to any demigod. Bhakti can be rendered only to Visnu (sravanam kirtanam visnoh). Thinking the Absolute Truth to be without form, the Mayavadis say that the word bhakti can apply to any form of worship. If this were the case, a devotee could imagine any demigod or any godly form and worship it. This, however, is not the real fact. The real fact is that bhakti can be applied only to Lord Visnu and His expansions. Therefore bhakti-lata is drdha-vrata, the great vow, for when the mind is completely engaged in devotional service, the mind does not fall down. If one tries to advance by other means — by karma-yoga or jñana-yoga — one will fall down, but if one is fixed in bhakti, he never falls down.
Thus from bhakti-lata the son Drdhacyuta is born, and from Drdhacyuta the next son, Idhmavaha, is born. The word idhma-vaha refers to one who carries wood for burning in a sacrifice when approaching a spiritual master. The point is that bhakti-lata, the cult of devotion, fixes one in his spiritual position. One so fixed never comes down, and he begets children who are strict followers of the sastric injunctions. As said in the Vedas:
tad-vijñanartham sa gurum evabhigacchet
samit-panih srotriyam brahma-nistham
In the line of devotional service, those who are initiated are strict followers of the Vedic scriptural injunctions.