SB 5.1.4

saṁśayo ’yaṁ mahān brahman
 dārāgāra-sutādiṣu
saktasya yat siddhir abhūt
 kṛṣṇe ca matir acyutā
Word for word: 
saṁśayaḥ — doubt; ayam — this; mahān — great; brahman — O brāhmaṇa; dāra — to the wife; āgāra — home; suta — children; ādiṣu — and so on; saktasya — of a person attached; yat — because; siddhiḥ — perfection; abhūt — became; kṛṣṇe — unto Kṛṣṇa; ca — also; matiḥ — attachment; acyutā — infallible.
Translation: 
The King continued: O great brāhmaṇa, this is my great doubt. How was it possible for a person like King Priyavrata, who was so attached to wife, children and home, to achieve the topmost infallible perfection in Kṛṣṇa consciousness?
Purport: 

King Parīkṣit wondered how a person so attached to wife, children and home could become so perfectly Kṛṣṇa conscious. Prahlāda Mahārāja has said:

matir na kṛṣṇe parataḥ svato vā
 mitho ’bhipadyeta gṛha-vratānām

A gṛhavrata, one who has taken a vow to execute family duties, has no chance to become Kṛṣṇa conscious. This is because most gṛhavratas are guided by sense gratification and therefore gradually glide down to the darkest regions of material existence (adānta-gobhir viśatāṁ tamisram). How can they possibly become perfect in Kṛṣṇa consciousness? Mahārāja Parīkṣit asked Śukadeva Gosvāmī to resolve this great doubt.