The favorable conditions for discharging devotional service are that one should be very enthusiastic in serving the Lord. The Lord in His form of Śrī Caitanya Mahāprabhu wanted the cult of devotional service to the Lord to be preached all over the world, in every nook and corner, and therefore a pure devotee's duty is to discharge this order as far as possible. Every devotee should be very enthusiastic, not only in performing his daily rituals of devotional service, but in trying to preach the cult peacefully by following in the footsteps of Lord Caitanya. If he is not superficially successful in such an attempt, he should not be deterred from the discharge of his duty. Success or failure has no meaning for a pure devotee because he is a soldier in the field. Preaching the cult of devotional service is something like declaring war against materialistic life. There are different kinds of materialists, such as the fruitive workers, the mental speculators, the mystic jugglers, and so many others. All of them are against the existence of Godhead. They would declare that they are themselves God, although in every step and in every action they are dependent on the mercy of the Lord. Therefore a pure devotee may not associate with such gangs of atheists. A strong devotee of the Lord will not be misled by such atheistic propaganda of the nondevotees, but a neophyte devotee should be very cautious about them. A devotee should see to the right discharge of devotional service under the guidance of a bona fide spiritual master and should not stick only to the formalities.
(Srimad Bhagavatam-------2:8:21-------purport).

Yes. Arjuna is asking that "You say that Kṛṣṇa consciousness is very good. Why You are engaging me in this fight?" That is his question. So Kṛṣṇa will answer this question. General people understand that retiring from ordinary duties, one becomes spiritually advanced. That is being taught here. It is not like that. Kṛṣṇa taught to the whole world that Arjuna was a soldier, he was a fighter, and in his fighting also he can be Kṛṣṇa conscious. It is not that he has to cease from fighting and then become Kṛṣṇa conscious. No. There is no such question. There is no rejection of anything, but dovetailing everything. That is the process. Do everything, but in Kṛṣṇa consciousness. If you are a fighter, fight, but for Kṛṣṇa. If you are a businessman, all right. Do business for Kṛṣṇa. If you are something else, do that, but for Kṛṣṇa. This is wanted. This is called Kṛṣṇa consciousness. To dovetail everything with Kṛṣṇa.
(Lecture on Bhagavad-Gita------3:1-5------purport).

So Lord Caitanya's movement is also fighting, but it is a fight in a different way. So the soldiers, Nityānanda Prabhu, soldier, was sent to deliver Jagāi-Mādhāi. This is also fighting. Therefore all the devotees, all the preachers of Kṛṣṇa consciousness movement, they are mahā-bāhu, strongly armed by the weapons of Kṛṣṇa. They cannot be defeated. They will push on the fight with māyā, this illusion. What is that illusion? The living entity under illusion is thinking that he will be happy by material comforts. That is not possible. So this movement, Kṛṣṇa consciousness movement, is a declaration of war with māyā. Declaration of war, but in a different way—by this chanting process: Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare. The transcendental vibration will clarify the whole atmosphere, and as soon as these Kṛṣṇa conscious soldiers comes out victorious, the whole world will be peaceful.
(Lecture on Bhagavad-Gita------7:4-5------purport).