Krishna consciousness is natural. It is already in everyone's heart. "Natural. Just like the children here, they are also dancing with their parents. They are offering flower, trying to imitate how to chant. Naturally. And they are very much pleased."
We should regularly attend the temple to hear about Krishna. Prabhupada tells how in one rich family's temple in Kanpur, the mother would fine the members of her family if they did not go to the temple. He says we should also do like that. "Anyone who is not attending mangala-arati should be fined. And the fine should be that he must sell one Krishna book."
He explains children born in such families where worship is practiced, imitate the worship, and become attracted by it, so much so they do not give it up.
"So nitya-siddha means he does not get covered by the influence of material nature about his natural devotional tendency to serve Krishna. . . . This is difference. Krishna gives him chance to get birth in such a family. Just like Pariksit Maharaja, that he never gets the chance of forgetting Krishna. So one who does not get the chance of forgetting Krishna is called nitya-siddha."
"A child cannot become a jnani. A child cannot become a yogi. But a child can become a bhakta. Therefore this is the easiest process. Pleasing. Everyone is pleased to execute this process."
He concludes by quoting the verse (SB 10.1.4) which describes that the animal killer or one who is killing himself will not be attracted to this simple, joyful process of hearing the glories of the Lord. Thus we prohibit animal killing as it is the greatest disqualification for understanding the Lord's glories.