Bhakti-rasāmṛta-sindhu .8.48
Blended reading (Sanskrit + English inline)
… although its actual position is as the main or prominent loving feeling of a devotee. When an unconstitutional ecstasy of devotional service is manifested prominently at a certain time, it is still accepted as the part. If it is not very prominently manifested, it appears only slightly and merges quickly back into the whole.
The word anādi (without beginning) is indicatory only (It represents the condition of the eternal associates, but the principle should also apply to those who have achieved a primary rasa by sādhana as well.) Thus anādi indicates only that the primary rasa has been previously firmly established. It is not like the vyabhicāri-bhāvas or secondary rasas. This comparison is used to indicate the difference of the main rasa in the devotee from the others. Though the vyabhicāri-bhāvas and secondary rasas disappear, the main primary rasa does not.
My note
Source: vedabase.io