The human life is meant for attaining eternal and unlimited happiness by spiritual realization.
Srimad Bhagavatam 1.3.13
The cause of misery is our perception. Self Realization means to come to the right perception.
As a highly potent drug injected intravenously acts at once on the whole body, the transcendental topics of the Lord injected through the ear of the pure devotee of the Lord can act very efficiently. Aural realization of the transcendental messages implies total realization, just as fructification of one part of a tree implies fructification of all other parts. This realization for a moment in the association of pure devotees like Sukadeva Gosvami prepares one's complete life for eternity.
When we read Srila Pabhupada’s purports, we become enriched with devotion. This happens because they are written with realization.