Simply by associating with a pure devotee, one becomes wonderfully advanced in Krishna Consciousness. Sadhu-sanga, or association with a devotee, means always engaging in Krishna Consciousness by chanting the Hare Krishna mantra but he whose heart is contaminated sees things differently. Therefore by sat-sanga, or association with devotees, one becomes perfectly pure in heart.
A devotee searches out a pure devotee and simply by his association becomes more advanced in spiritual consciousness than any yogi.
One must seek the association of persons who are Krishna Conscious and who engage in devotional service. Without such association one cannot make advancement.
If we actually want spiritual advancement, we have to be willing to perform tapasya to attract the attention of God to show Him we are serious, to show Him that we are depending on His causeless mercy.
99% of our spiritual advancement depends on the quality of our chanting.
Chanting before the deities, Tulasi and Sad-guru gives quick advancement.