Transcendental benefit of serving Vaishnavas

After getting blessings from Lord Vishnu, Prthu Maharaj instructed his citizens after performing another yagna. He instructed them on various aspects like following varnashrama duies,etc and also speficially talked about respecting and serving the brahamans and the vaishnavas.

The following verses spoken by him are wonderful in how they inspire one to serve the brahamana and the vaishnavas and also set the expectation that the Supreme Lord has from us.
Synopsis:

1. The Supreme Lord Himself engages in the service of brahamanas and vaishnavas
2. The Lord is pleased if we engage in their service as He is dear to them and they are dear to Him.
3. Be regular service one's heart becomes cleaned and one can get liberation from material attachment and still be very blissful and satisfied.
4. One is relieved from sinful reactions
5. One develops all good and desirable qualities.
   
6. It is more superior that any fruitive activity.
7. It is pleasing to the demigods who one tries to please by performing sacrifices
   

SB 4.21.39: The Supreme Personality of Godhead, who is everlastingly independent and who exists in everyone's heart, is very pleased with those who follow in His footsteps and engage without reservation in the service of the descendants of brāhmaṇas and Vaiṣṇavas, for He is always dear to brāhmaṇas and Vaiṣṇavas and they are always dear to Him.

SB 4.21.40: By regular service to the brāhmaṇas and Vaiṣṇavas, one can clear the dirt from his heart and thus enjoy supreme peace and liberation from material attachment and be satisfied. In this world there is no fruitive activity superior to serving the brāhmaṇa class, for this can bring pleasure to the demigods, for whom the many sacrifices are recommended.

SB 4.21.41: Although the Supreme Personality of Godhead, Ananta, eats through the fire sacrifices offered in the names of the different demigods, He does not take as much pleasure in eating through fire as He does in accepting offerings through the mouths of learned sages and devotees, for then He does not leave the association of devotees.

SB 4.21.42: In brahminical culture a brāhmaṇa's transcendental position is eternally maintained because the injunctions of the Vedas are accepted with faith, austerity, scriptural conclusions, full sense and mind control, and meditation. In this way the real goal of life is illuminated, just as one's face is fully reflected in a clear mirror.

SB 4.21.43: O respectable personalities present here, I beg the blessings of all of you that I may perpetually carry on my crown the dust of the lotus feet of such brāhmaṇas and Vaiṣṇavas until the end of my life. He who can carry such dust on his head is very soon relieved of all the reactions which arise from sinful life, and eventually he develops all good and desirable qualities.

SB 4.21.44: Whoever acquires the brahminical qualifications — whose only wealth is good behavior, who is grateful and who takes shelter of experienced persons — gets all the opulence of the world. I therefore wish that the Supreme Personality of Godhead and His associates be pleased with the brāhmaṇa class, with the cows and with me.