Are ALL devotees of Lord Shiva cursed by Rishi Bhrigu to follow anti-Vedic principles?
According to Sri Chaitanya Mahaprabhu, Bhrigu's curse is not applicable to all devotees of Shiva. It is only applicable to those who worship Lord Shiva as different from or superior to Lord Vishnu:
After bathing in Bindu-Sarovara and taking darshana of Sri Bhuvaneshvara, the all- opulent Lord, Sri Krishna Chaitanya sat contentedly, wholly immersed in the bliss of prema. Mahaprabhu then ate choice foods prepared by the bhaktas, and afterwards as He rested contentedly, He contemplated the lotus feet of Sri Krishna.
The illustrious Lord thought, "If somehow the maha-prasadam of the trident-wielding god of gods could be obtained, then we could truly take pleasure." As He was reflecting thus, a certain Brahmana came before Him, bearing in his hands a small portion of Mahadeva's prasadam.
He said, "Please accept this prasadam of Mahadeva." Hearing this, Lord Gaura at once stood up and accepted the prasadam with bowed head. They all gathered together around the maha-prasadam, and the Lord honored it with His servants as though it were immortal nectar. Thus Gaura Hari showed how dear Shiva is to Lord Krishna. Again Gaura Hari arose very early in grat happiness, and after bathing quickly in Bindu-Sarovara, He bowed before Lord Shiva and then left on His way.
When the powerful brahmana Sri Damodara Pandita heard that the Lord had eaten the remnants of Shiva's food, He said, "One should not eat the remnants of Lord Shiva because Bhrigu Muni has placed a curse on those who worship him. Why then did the all-opulent transcendental Lord, knowing this, eat that food?"
Hearing this, Murari replied to the noble vipra, "Hear from me the reason for which the Lord ate those nectarean remnants of Lord Shiva."
When Sri Krishna Chaitanya made His auspicious arrival, Mahadeva joyously accepted Him as an honored guest. Please hear somewhat further. When bhaktas worship Mahadeva thinking of him as the best among Vaishnavas, Maheshvara accepts that offering from them, and that food should be considered great and pure prasadam. Those who in a sectarian spirit differentiate between Sri Krishna and his bhaktas indeed fall down. Sri Hari personally advented in the form of a bhakta as Chaitanya Mahaprabhu in order to instruct such inimical persons. The Lord of all gods, who is the supreme controller of the cosmic manifestation, certainly seeks to benefit all embodied beings. Thus, by His reverential acceptance of Lord Shiva's food-remnants, He teaches them by His example. Wherever the lingam is established and worshipped with a conception that Lord Shiva and Sri Hari have separate parties, there Bhrigu's curse will act, because of this offense of a dualistic concept. Hari and Sankara have one interest. If in the presence of a Shiva liìgam someone worships Them without a dualistic concept, the curse will not have effect. By people understand Their unity of interest, love will increase for both Hari and Shankara, and worship for Them both will increase. By tasting such maha-prasadam one can attain liberation, be cured from terrible diseases, and obtain undisturbed prosperity. Those who out of delusion do not eat such maha-prasadam become offenders to both Hari and Shiva. They become diseased and bereft of opulence. Wherever the beginningless lingam of Lord Shiva is worshipped with great respect by Vaishnavas in order to develop love for Shri Krishna, there will be no doubt about accepting the remnants of Lord Shiva's food. O vipra, such devotional service is verily auspicious for all embodied beings.
(From Sri Krishna Chaitanya Charitra Mahakavyam, Canto 3, Sarga 9)
So basically one should worship Lord Shiva keeping in mind that He's non-different from Lord Vishnu.
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