Once Srila Bhaktisiddhanta Saraswati Thakur was asked by a devotee that why is it that sometimes we find that devotees are chanting 16 rounds, following the 4 regulative principles, following all the rules of sadhana-bhakti for so much time and yet we find so much?
Srila Bhaktisiddhanta Saraswati Thakur told a story to answer the question. He said once there was a marriage party, and the marriage was supposed to be held the following day morning in the village of the bride, so the groom and his family left for the village that night. They hired a boat and the boatman was a very experienced person. Soon the boatman began rowing and since it was night time, the family and groom fell off to sleep. The entire night the boatman was sincerely rowing the boat and rowing and rowing until it was sunrise. The family got up and when they saw around, they were shocked. They had not moved an inch. They yelled at the boatman asking him, why he did not move even an inch. The boatman exclaimed that he has been rowing the boat all night and till now he is doing that. An experienced person of the family saw the situation and commented that the boat did not move because the boatman forgot to pull the anchor.
What was the anchor? The anchor is our motivation to become the proprietor, enjoyer and controller. It's our selish desire. We have to have the intent to pull them up and resisting these tendencies in us. Then our sadhana will give us really good progress. Lord Chaitanya Mahaprabhu explained that the bhakti-lata bija is like a little seed, and our sadhana is the water that makes the seed grow but along with the seed, many weeds also grow. So we have to identify the weeds and pull them up or else the same water which is watering the creeper of devotion, will water the weeds. These weeds refer to selfishness, egoism, fault-finding. If we are not careful with these weeds and water them thinking we are watering our bhakti-lata bija, then we become hard-hearted and mean and not compassionate.
A crude example – A knife in the hand of a surgeon can save a life and a knife in the hand of a criminal can take a life. So our consciousness and intent of performing sadhana bhakti is what matters.
Srila Prabhupada would say to take this Krsna Consciosuness sincerely which means without ulterior motives. It means we have to do tapasya by accepting all that is favourable for our devotional service and rejecting all that is unfavourable for our devotional service. If we become proud of our knowledge or any other qualities that Krishna has bestowed, then we become like any other staunch material religionist who is entangled in the ritualistic aspects of religion and overlooks the goal of love for God and His children.
Therefore, Chaitanya Mahaprabhu advised us to be gopi-bharthu pada-kamalayor dasa-dasanudasa - being secured in the position of the servant of the servant of the servant of the Lotus feet of the Lord of the Gopis.