As stated in Bhagavad-gītā (3.21):

yad yad ācarati śreṣṭhas
 tad tad evetaro janaḥ
sa yat pramāṇaṁ kurute
 lokas tad anuvartate

“Whatever action is performed by a great man, common men follow in his footsteps. And whatever standards he sets by exemplary acts, all the world pursues.”

For his own sense gratification, King Indra thought to defeat Mahārāja Pṛthu in the performance of one hundred horse sacrifices. Consequently he stole the horse and hid himself amid so many irreligious personalities, taking on the false guise of a sannyāsī. Such activities are attractive to the people in general; therefore they are dangerous. Lord Brahmā thought that instead of allowing Indra to further introduce such irreligious systems, it would be better to stop the sacrifice. A similar stance was taken by Lord Buddha when people were overly engrossed in the animal sacrifices recommended by Vedic instructions. Lord Buddha had to introduce the religion of nonviolence by contradicting the Vedic sacrificial instructions. Actually, in the sacrifices the slaughtered animals were given a new life, but people without such powers were taking advantage of such Vedic rituals and unnecessarily killing poor animals. Therefore Lord Buddha had to deny the authority of the Vedas for the time being. One should not perform sacrifices that will induce reversed orders. It is better to stop such sacrifices.

As we have repeatedly explained, due to a lack of qualified brahminical priests in Kali-yuga, it is not possible to perform the ritualistic ceremonies recommended in the Vedas. Consequently the śāstras instruct us to perform the saṅkīrtana-yajña. By the saṅkīrtana sacrifice, the Supreme Personality of Godhead, in His form of Lord Caitanya, will be satisfied and worshiped. The entire purpose of performing sacrifices is to worship the Supreme Personality of Godhead, Viṣṇu. Lord Viṣṇu, or Lord Kṛṣṇa, is present in His form of Lord Caitanya; therefore people who are intelligent should try to satisfy Him by performing saṅkīrtana-yajña. This is the easiest way to satisfy Lord Viṣṇu in this age. People should take advantage of the injunctions in different śāstras concerning sacrifices in this age and not create unnecessary disturbances during the sinful Age of Kali. In Kali-yuga men all over the world are very expert in opening slaughterhouses for killing animals, which they eat. If the old ritualistic ceremonies were observed, people would be encouraged to kill more and more animals. In Calcutta there are many butcher shops which keep a deity of the goddess Kālī, and animal-eaters think it proper to purchase animal flesh from such shops in hope that they are eating the remnants of food offered to the goddess Kālī. They do not know that the goddess Kālī never accepts nonvegetarian food because she is the chaste wife of Lord Śiva. Lord Śiva is also a great Vaiṣṇava and never eats nonvegetarian food, and the goddess Kālī accepts the remnants of food left by Lord Śiva. Therefore there is no possibility of her eating flesh or fish. Such offerings are accepted by the associates of the goddess Kālī known as bhūtas, piśācas and Rākṣasas, and those who take the prasāda of the goddess Kālī in the shape of flesh or fish are not actually taking the prasāda left by the goddess Kālī, but the food left by the bhūtas and piśācas.