Arjuna fought because he thought that, "This war, this Kurukṣetra battle, is for the satisfaction of Kṛṣṇa." Kariṣye vacanaṁ tava (BG 18.73). In the beginning, Arjuna denied to fight. He thought, "Why shall I fight with my kinsmen? Let them enjoy." But when he understood that, "It is Kṛṣṇa's desire . . ." Nimitta-mātraṁ bhava savyasācin: "It is already planned." Kṛṣṇa said: "My dear Arjuna, you are thinking that you'll save your relatives, but you are wrong. It is already planned. Those who have come here, they must be killed. That is already My plan. You simply become a instrument." Nimitta-mātraṁ bhava savyasācin. So when Arjuna understood that, "It is the Kṛṣṇa's plan. That I am servant of Kṛṣṇa; I must satisfy Kṛṣṇa," Arjuna therefore asked . . . Kṛṣṇa therefore asked Arjuna, "Now, after hearing My instruction in the Bhagavad-gītā, what you are going to do?" Kṛṣṇa said . . . Arjuna replied, naṣṭo mohaḥ smṛtir labdhā: "My Lord Kṛṣṇa, my illusion is now over." Smṛtir labdhā, "I have got my remembrance. Everything belongs to You. For Your satisfaction everything must be done." Kariṣye vacanaṁ tava (BG 18.73). "Yes, I'll fight."
This is Kṛṣṇa consciousness. So long you think it is for your satisfaction, that is material. And as soon as you think, as soon as you understand that everything belongs to Kṛṣṇa and everything should be used for the service of Kṛṣṇa, that is spiritual. That is the distinction between material and spiritual. There is nothing like that material . . . spiritually something wonderful. But everything . . . Īśāvāsyam idaṁ sarvam (ISO 1). If everything belongs to Kṛṣṇa, where is material? There is nothing material.
Everything is spiritual, but we do not know how to use it; therefore it is material. When you forget Kṛṣṇa, when it forget the proprietorship of Kṛṣṇa upon everything, that is material. Hari-sambandhe. Kṛṣṇa-sambandhe. Nirbandhaḥ kṛṣṇa-sambandhe yuktaṁ vairāgyam ucyate. This is the injunction of the Gosvāmīs, that we have to accept everything as Kṛṣṇa. That is the fact.