This means in a way that the truth is impersonal. It's not something that originates with our ego self. It's not coming from our interpretations or ego learning. It's not defined by our opinions. It's sort of in a way, "outside of us", or at least outside of the ego.
The truth is something that we open up to, listen to, trust, and allow to define things FOR us. We need to learn to let it choose for us, tell us what IT is on ITS own terms, and LISTEN to it. We need to regard it as guidance, listen to that guidance, trust it and ACT on it.
What you believe is true you will be willing to act on. Actions speak louder than words. If you do not believe something is true, you will not base your actions on it as a foundation. But if you thoroughly DO believe something is true, you will be willing to DEMONSTRATE it. You will show everyone, in a teaching mode, and say.... "see?! Like this."
This is why we need to demonstrate miracles of healing, the undoing of sickness, the reversal of death, and the transcendence of all worldly causes. ONLY in this way can we show that we REALLY, really, really, believe that the truth is true, by acting on it and showing everyone that it is true. Otherwise the truth stays in the realm of theory, and just believing a theory is nothing but an idea.
This is why it is important not to just believe concepts. If they are not REALLY believed, they remain concepts. If they are LIVED and thus demonstrated, by example, then it has become the truth.