Characteristics of Vaidhi-sādhana-bhakti?

Now this sādhana-bhakti, or practice of devotional service, may also be divided into two parts. The first part is called service according to regulative principles: one has to follow these different regulative principles by the order of the spiritual master or on the strength of authoritative scriptures, and there can be no question of refusal. That is called vaidhi, or regulated. One has to do it without argument. Another part of sādhana-bhakti is called rāgānugā. Rāgānugā refers to the point at which, by following the regulative principles, one becomes a little more attached to Kṛṣṇa and executes devotional service out of natural love. For example, a person engaged in devotional service may be ordered to rise early in the morning and offer ārati, which is a form of Deity worship. In the beginning, by the order of his spiritual master, one rises early in the morning and offers ārati, but then he develops real attachment. When he gets this attachment, he automatically tries to decorate the Deity and prepare different kinds of dresses and thinks of different plans to execute his devotional service nicely. Although it is within the category of practice, this offering of loving service is spontaneous. So the practice of devotional service, sādhana-bhakti, can be divided into two parts—namely, regulative and spontaneous.

Rūpa Gosvāmī defines the first part of devotional practice, or vaidhi-bhakti, as follows: “When there is no attachment or no spontaneous loving service to the Lord, and one is engaged in the service of the Lord simply out of obedience to the order of the spiritual master or in pursuance of the scriptures, such obligatory service is called vaidhi-bhakti.”

— NoD chapter 2