The idea of this slogan is that in the sitting practice of meditation and with an understanding of ultimate bodhichitta, you actually transcend the seven types of consciousness, and rest in the eight consciousness, alaya.
The first six types of consciousness are the sensory perceptions: eye, ear, nose, tongue, body, and mind consciousness.
7. nuisance mind, neurosis
The idea of resting one’s mind in the basic alaya is to free oneself from that sevenfold mind and rest in simplicity and in clear and nondiscrimating mind.