Renouncement and Arahanthood
When Siddhartha was aged 29, he renounced the world to become an ascetic. Kaundinya, along with Bharika (Bhaddiya), Baspa (Wappa), Mahanama and Asvajit (Assaji), (variously described as four of the other scholars who had read Siddhartha's future, or the sons of those scholars) followed him into the ascetic life, with the approval of Suddhodarna who was worried about Siddhartha's safety. They were known as the Pancavaggiya (The group of Five) or Pancaka Bhadravargiya (The Group of Five Fortunate Ones). After Siddhartha had mastered all the teachings of Arada Kalama (Alara Kalama) and then Udraka Ramaputra (Uddaka Ramaputta), he left and began practicing self mortification along with Kaundinya and his four colleagues at Uruvilva (Uruvela). Kaundinya and his colleagues attended to Siddhartha in the hope that he would become enlightened through self-mortification. These involved self-deprivation of food and water, and exposing themselves to the elements to near-death for six years, at which point Siddhartha rejected self-mortification. Kaundinya and his colleagues became disillusioned, believing Siddhartha to have become a glutton and moved away to Mrgadava (Isipatana), near Varanasi to continue their practices.
After Siddhartha became the enlightened Gautama Buddha, he sought to find his former teachers Arada Kalama and Udraka Ramaputra in order to teach them. Realising that they had died, the Buddha decided to find Kaundinya and his colleagues to share his teachings. Kaundinya and his companions were skeptical of Gautama Buddha after his abandonment of asceticism, and initially refused to acknowledge his presence, except to offer a seat on the ground. However, the ascetics were soon won over when they sensed that the Buddha had changed since they left him. Gautama Buddha preached the Dhammacakkappavattana Sutta (Pali; Skt., Dharmacakra Pravartana Sutra), which deals with the Four Noble Truths and the Noble Eightfold Path, the core pillars of Buddhist teaching regarding the intrinsic suffering of existence and how to deal with it. Kaundinya reached the Sotapatti stage of arahanthood upon hearing this, becoming the first human to comprehend the teachings. The Buddha acknowledged this by remarking "annasi vata bho Kondanno (meaning "you have realised, Kondanna"). Five days later, hearing the subsequent Anattalakkhana Sutta regarding no-self or soul-lessness(Anatta), Kaundinya gained full arahantship. Kaundinya thus became first arahant. Having realised arahanthood, he requested the Buddha for permission to retire from the world, which was granted with the words "ehi bhikkhu". Kaundinya thus became the first bhikkhu (monk) in the Buddha's dispensation, known as the sangha. Later, the assembly at Jetavana declared him to be the foremost among the first bhikkhus and the disciples of long standing.
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