Six memories

six memories (六念).
Memories of
(1) the Buddha,
(2) the Dharma,
(3) the Saṅgha,
(4) the precepts,
(5) almsgiving, and
(6) heaven: ordinary beings should remember that rebirth in a heaven is acquired by purifying one’s mind, observing one’s precepts, and almsgiving, and that they can strive to qualify.

Riders of the Mahāyāna should remember the heaven of the highest meaning (第一義天), the ultimate nirvāṇa.

Source

www.sutrasmantras.info