Nothing is more effective than spending time in personal investigation and examination, taking the time to truly examine things such as impermanence or suffering. You can spend considerable time saying “that strikes me as being true,” but when you examine it, you’re completely convinced. In Buddhism, we talk about the importance of devotion, but faith and devotion are not merely agreeing with what somebody else says. The Buddha taught, in the first place, that [everything] has to be based on your personal investigation. It’s very much like the analogy of tasting honey - you know it’s sweet. If somebody comes along and says, “I’m going to kill you if you do not say honey is salty,” you may say that it’s salty—but deep down, you can’t do much about the mind that says it is sweet anyway. Similarly, [when you] spend time in personal investigative meditation, analyzing and examining whether something is true or not, then you experience [it] for yourself. 

~Khandro Rinpoche