Exact meaning
Srimad-Bhagavatam
SB Canto 3
The exact meaning of the word sattvena is given by Śrīdhara Svāmī as being synonymous with dhairyeṇa, or patience.
SB 3.29.16, Purport: 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.