The Buddha said a “noble disciple” who is free of greed, anger, and ignorance and who keeps pervading everything and every being in the cosmos with boundless loving-kindness, compassion, appreciation, and equanimity will receive four assurances.
The first assurance is if there is rebirth and retributions from good or ill karmas, then through his good karmas, he will have a good rebirth.
The second assurance is if rebirth does not exist, he will be happy in this lifetime, as he will feel neither greed or anger nor their attendant suffering.
The third assurance is if a person who commits bad karmas suffers the related retributions, the noble disciple will not suffer because he will never give rise to bad thoughts, utter bad words, or commit any bad actions.
The fourth assurance is if a person who commits bad karmas does not suffer the related retributions, then the noble disciple is purified anyway.