a.When Lord Rama’s incarnation came to an end, why did he take the beings of Ayodhya with him to Srivaikuntham? Was it due to their bhakti yoga, or because they had perfectly fulfilled sharanagati? b.In the Mahabharata, there’s a story about Krishna and Arjuna rescuing the children of a Brahmin and bringing them back from Vaikuntham. How did Lord Vishnu manage to bring these children and Arjuna from Vaikuntham when it is said that those who go to Vaikuntham will never return (na cha punarAvarttatE)?

a.Svami Desikan, in his Abhaya Pradhanam, explains that the people of Ayodhya were also included when Bharatazhwan performed sharanagati to Perumal at Chitrakuta. Thus, they too earned the merit of following that path.
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b.Those who reach Srivaikuntham through Archiradi marga do not return. It would not be accurate to say that one has attained moksha when Bhagavan took them and brought them back. So, it is more fitting to say that the Lord simply brought them out.