At Kapilavatthu. Seated to one side, the Buddha said to Nandiya the Sakyan:

“Nandiya, a noble disciple who has four things is a stream-enterer, not liable to be reborn in the underworld, bound for awakening.

What four? It’s when a noble disciple has experiential confidence in the Buddha … the teaching … the Saṅgha … And they have the ethical conduct loved by the noble ones … leading to immersion. A noble disciple who has these four things is a stream-enterer, not liable to be reborn in the underworld, bound for awakening.”