Both brāhmaṇas were pure Vaiṣṇavas. The younger man took special care of the older one simply to please Kṛṣṇa. In Śrīmad-Bhāgavatam (11.19.21) Kṛṣṇa says, mad-bhakta-pūjābhyadhikā: “It is better to render service to My devotee.” Thus, according to the Gauḍīya-Vaiṣṇava philosophy of Caitanya Mahāprabhu, it is better to be a servant of the servant of God. One should not try to serve Kṛṣṇa directly. A pure Vaiṣṇava serves a servant of Kṛṣṇa and identifies himself as a servant of a servant of Kṛṣṇa. This is pleasing to Lord Kṛṣṇa. Śrīla Narottama dāsa Ṭhākura confirms this philosophy: chāḍiyā vaiṣṇava-sevā nistāra peyeche kebā. Unless one serves a liberated Vaiṣṇava, he cannot attain liberation by directly serving Kṛṣṇa. He must serve the servant of Kṛṣṇa.