In Lord Chaitanya's instructions to Rupa Gosvami, He explains how the bhaktilata-bija (the seed of the creeper of devotional service) is given by the spiritual master to the disciple. When the Holy Name of the Lord is given, the seed is planted; but one has to continue to water that seed by hearing. That is the actual connection between the spiritual master and the disciple. The disciple is fully dependent upon having that seed watered. Without watering a seed, what happens? It cannot grow—or as Lord Chaitanya explains: If we are not careful while the devotional plant is being watered, the the weeds are being watered at the same time. What are these weeds? They are the anarthas within our heart.
MKV, Vol 2- Pg 6, (Initiation Lecture—Kiev, Ukraine—15/11/01)