There are four traps to Buddhist practitioners (monks, nuns, and lay people):
1. Sensual pleasures: all impermanent pleasures the senses bring about. These pleasures attract and tie us up like fetters. Once we are trapped by these pleasures, we are vulnerable to mara/evils, and the inevitable results are samsara/sufferings.
2. Knowledge and intellectual capacities (analysis, arguments....): Be careful about the knowledge we accumulate. They nurture our arrogance, self love, and pride. Our illusory ideas in discourse analysis and arguments only drive us away from the Buddha Nature. These hinder or make it difficult for us to understand the Ultimate Nature, and to meditate and concentrate.
3. Rituals and formalities: Do not become a practitioner who is well verse in chanting and performing religious ceremonies or rituals. These forms do not lead us to enlightenment, for all forms are unstable, and will change by themselves.
4. Self and Self love: The biggest obstacle to Buddhist practitioners. Illusory thoughts keep arising from the self (the "I") and self love, and all that are attached to it. All discriminative ideas originate from these "self" and "self love."