Sree Sree Guru Gaurangau Jayatah!
You have already heard several times from vaishnavas that the real self of the jiva is the eternal servant of Supreme Lord Sri Krishna and when he forgets his relation with Sri Krishna and is enveloped by the illusory energy, he is hurled down in this material world to receive the punishment for his aversion to Sri Krishna, for his reluctance to serve Krishna. The conditioned souls, due to forgetfulness of their relation to Sri Krishna, are passing through cycles of births and deaths from time immemorial. It is not so easy for them to change their propensity to enjoy this world. Even a person who starts drinking wine and becomes habituated to it cannot give up his bad habit all of a sudden, despite understanding fully well that intoxication is bad for him. In the like manner, we have imbibed through cycles of births and deaths, so many various propensities in this world. It will take time to change our habits. For that if we lose patience, we cannot get the objective. Sadhana vinu sadhya-vastu keha nahi paya--nobody can get his objective without performing penance for it. A neophyte to devotional practice may be restless at any moment, if he does not get actual association of a bona fide suddha bhakta. It is not so easy to get such association in this material world, at least in western countries where they are more inclined for material enjoyments. We should not be disappointed by this. If we are sincere we will never be deceived and Krishna will protect us. God is All-Merciful and His personal associates are also All-Merciful.
You should remember four Narsimha mantras, each four times, as well as Pancha-tattva and Mahamantra, each four times before going to bed and after rising up from bed.
Narsimha Bhagavan can remove all ulterior desires and bestow pure devotion to Him.
--- Jagad-guru His Divine Grace Srila Bhakti Ballabh Tirtha Goswami Maharaj