What is the primary thought a devotee can have to maintain a constant faith? A devotee can have a constant faith by possessing the complete conviction that simply by serving the Supreme Lord Śrī Kṛṣṇa, all perfection can be achieved. This faith is achieved by performing the devotional service and the singing of "Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/Rāma, Hare Rāma, Rāma Rāma, Hare Hare", which purifies the heart. One must also control the senses. The firm conviction of executing the Lord's order, believing that rendering devotional service to the Lord Kṛṣṇa automatically carries out all other activities, is true faith. This faith is created through association with devotees.