Whenever a devotee is in distress or has fallen into difficulty, he thinks that it is the Lord's mercy upon him. He thinks, "Thanks to my past misdeeds I should suffer far, far greater than I am suffering now. So it is by the mercy of the Supreme Lord that I am not getting all the punishment I am due. I am just getting a little, by the mercy of the Supreme Personality of Godhead." Therefore he is always calm, quiet and patient, despite many distressful conditions.
(Bhagavad-Gita--12:13-14--purport).

A devotee is always free from all bad association. Sometimes one is praised and sometimes one is defamed; that is the nature of human society. But a devotee is always transcendental to artificial fame and infamy, distress or happiness. He is very patient. He does not speak of anything but the topics about Kṛṣṇa; therefore he is called silent.
(Bhagavad-Gita--12:18-19).

The exact meaning of the word sattvena is given by Śrīdhara Svāmī as being synonymous with dhairyeṇa, or patience. One must perform devotional service with great patience. One should not give up the execution of devotional service because one or two attempts have not been successful. One must continue. Śrī Rūpa Gosvāmī also confirms that one should be very enthusiastic and execute devotional service with patience and confidence. Patience is necessary for developing the confidence that "Kṛṣṇa will certainly accept me because I am engaging in devotional service." One has only to execute service according to the rules and regulations to insure success.
(Srimad Bhagavatam--3:29:16--purport).

Real success in yoga comes only by fully surrendering to His lotus feet. However, since it is not possible to attain such a mood of complete surrender in a moment, we should also not expect the Lord's mercy to manifest before us instantaneously. Although the Lord, and sometimes even His devotees, perform miracles, still we must not expect such extraordinary things to happen to us. Of course, it is certain that the degree of mercy the Lord bestows upon us is much greater than our degree of surrender to Him. Another danger is this: If we were to receive all His mercy at once, we would become corrupt and fallen, like many yogīs who attain mystic perfection. Better that we continue to perform our duties in a regulated way, with patience and enthusiasm; then undoubtedly we will receive the Lord's full mercy.
(Renunciation Through Wisdom).