The Kṛṣṇa consciousness movement has spread all over the world within a very short time (within five years), and mundane people are very astonished at this. However, by the grace of Lord Śrī Caitanya Mahāprabhu, we understand that everything is possible by the grace of Kṛṣṇa. Why does Kṛṣṇa have to take five years? In five days He can spread His name and fame all over the world like wildfire. Those who have faith in and devotion to Kṛṣṇa can understand that these things happen so wonderfully by the grace of Śrī Caitanya Mahāprabhu. We are simply the instruments. In the fierce Battle of Kurukṣetra, Arjuna was victorious within eighteen days simply because Kṛṣṇa’s
grace was on his side.
yatra yogeśvaraḥ kṛṣṇo
yatra pārtho dhanur-dharaḥ
tatra śrīr vijayo bhūtir
dhruvā nītir matir mama
“Wherever there is Kṛṣṇa, the master of all mystics, and wherever there is Arjuna, the supreme archer, there will also certainly be opulence, victory, extraordinary power and morality. That is my opinion.” (Bg. 18.78)
If the preachers in our Kṛṣṇa consciousness movement are sincere devotees of Kṛṣṇa, Kṛṣṇa will always be with them because He is very kind and favorable to all His devotees. Just as Arjuna and Kṛṣṇa were victorious in the Battle of Kurukṣetra, this Kṛṣṇa consciousness movement will surely emerge victorious if we but remain sincere devotees of the Lord and serve the Lord according to the advice of predecessors (the six Gosvāmīs and other devotees of the Lord). As Narottama dāsa Ṭhākura has stated: tāṅdera caraṇa sevi bhakta-sane vāsa, janame janame haya ei abhilāṣa. The Kṛṣṇa consciousness devotees must always desire to remain in the society of devotees. Bhakta-sane vāsa: they cannot go outside the Kṛṣṇa conscious society or the movement. Within the society we must try to serve the predecessors by preaching Caitanya Mahāprabhu’s cult and spreading His name and fame all over the world. If we attempt this seriously within the society, it will be successfully done. There is no question of estimating how this will happen in the mundane sense. But without a doubt, it happens by the grace of Kṛṣṇa.
Ref >> Srila Prabhupada Vani.