Mahayana (meaning the “Greater Vehicle” in Sanskrit) brought a new way of looking human salvation, and therefore human destiny.
In the earlier Buddhist doctrine, one had to gradually accumulate merit from good behavior in countless lifetimes before one could ever hope to become a Buddha.
But Mahayana offered a shortcut to nirvana in one’s present lifetime.
The means to that shortcut was to awaken one’s own inner Buddha Nature (bodhicitta) through a process of purification involving techniques such as meditation and faith in various Mahayana Buddhas and bodhisattvas.