He strives with might and main along the Path, searches it out, accustoms himself to it; to that end does he make firm his self-possession, to that end does he hold fast in effort, to that end does he remain steadfast in love towards all beings in all worlds; and still to that does he direct his mind again and again, until gone far beyond the transitory, he gains the Real, the highest fruit. And when he has gained that, the man who has ordered his life aright has realized nirvana [oneness].
Milindapanha IV 8, 84