Sri Narada-bhakti-sutra, purpoprt to Sutra 5:
The next item favorable for devotional service is niscaya, confidence. When one becomes disappointed in his service to the Supreme Lord, that disappointment must be rejected and replaced with confidence in attaining the ultimate goal, love of Godhead. The devotee should patiently follow the rules and regulations of devotional service so that the day will come when he will achieve, all of a sudden, a

