A Mahā Brahmā, whose name means “ever young”. In the Nikāyas DN.i.121 MN.i.358 SN.i.153 AN.v.327 he is mentioned as the author of a famous verse, which is eleswhere attribued to the Buddha. SN.ii.284 Sanaṅkumāra is represented as a very devout follower of the Buddha.
In a sutta of the Saṃyutta, SN.i.153 he is spoken of as visiting the Buddha on the banks of the Sappinī, and it was during this visit that the above verse was spoken. Sanaṅkumāra was present at the preaching of the Mahāsamaya Sutta. DN.ii.261
In the Janavasabha Sutta, Janavasabha describes to the Buddha an occasion on which Sanaṅkumāra attended an assembly of the Devas, presided over by Sakka and the Four Regent Gods. There was suddenly a vast radiance, and the devas knew of the approach of Sanaṅkumāra. As the usual appearance of the Brahmā is not sufficiently materialized for him to be perceived by the Devas of Tāvatiṃsā, he is forced to appear as a relatively gross personality which he specially creates. As he arrives, the Devas sit in their places with clasped hands waiting for him to choose his seat. Then Sanaṅkumāra takes on the form of Pañcasikha and sits, above the assembly, cross legged, in the air. So seated, he expresses his satisfaction that Sakka and all the Tāvatiṃsā Devas should honour and follow the Buddha. His voice has all the eight characteristics of a Brahmā’s voice. DN.ii.211 He then proceeds to create thirty three shaper, of himself, each sitting on the divan of a Tāvatiṃsā Deva, and addresses the Devas, speaking of the advantages of taking refuge in the Buddha, the Dhamma and the Saṅgha. Each deva fancies that only the shape sitting on his own divan has spoken and that the others are silent. Then Sanaṅkumāra goes to the end of the Hall, and, seated on Sakka’s throne, addresses the whole assembly on the four ways of iddhi; on the three avenues leading to Bliss, as manifested by the Buddha; on the four satipaṭṭhānas, and the seven samādhiparikkhārā. He declares that more than twenty four lakhs of Māgadha disciples, having followed the teachings of the Buddha, have been born in the deva worlds. When Sanaṅkumāra has finished his address, Vessavaṇa wonders if there have been Buddhas in the past and will be in the future. The Brahmā reads his thoughts and says there certainly were and will be.