In plain words
They have been experiencing it as a Vedic tradition. They have been practising it. But this has no bond at all with true Bhakti.
If we are to recognise true Bhakti, we can come to recognise what this Bhakti is only when we firmly believe the truth that the jīvātma is nothing but a portion of God. God is the original, the devotee is the reflection. First of all we must recognise the truth that the jīva is nothing but a portion of the Paramātma. As long as there is the feeling that God is separate and the devotee separate, this will not be called Bhakti. As long as such a difference remains, such a one cannot worship God lastingly. That is why devotees do bhajans, dhyāna, japa and yogas for some time, and then, little by little, that Bhakti and devotion dwindle, until in the end they lose faith itself. The reason: the very feeling of difference, that God is separate and I am separate, is its root cause. One who holds such a difference cannot become a devotee. We must recognise that the sparks that leap out of a fire are not separate from the fire. Just as fire has the power to burn and has radiance, those powers are in this spark too. So in the devotee too, a portion of God, Sat, Cit and Ānanda, God's own nature, must have come forth. God is the embodiment of Prema. So in the devotee too, His reflection, this Prema is there as his nature. Then such a devotee, a reflection and a portion, should be experiencing this very Prema always; so where is the opening for these bad qualities to enter, anger, hatred, envy, pride, Ahaṅkāra and the like? A doubt like this may arise in us. Well, because the Prema that is in this jīva enters into outward-turned objects, the heart of Prema becomes soiled. In this soiled heart the seal of God cannot show itself clearly. Only when the Prema of this devotee, the reflection, recognises omnipresence, omniscience and omnipotence can this principle of God be recognised clearly in oneself. Though divinity is in him, he becomes powerless to recognise it. The reason is nothing but separateness. Does the sweet juice in a fruit know itself? Do the creepers enjoy the nectar in a flower? Does the book enjoy the sweet essence in a scripture? The fruit was born on the tree itself. But the tree did not know the sweetness of that fruit at all. There is holy nectar in flowers, but the creepers do not enjoy it.