I was posed a question recently in conversation on how somebody can determine if someone is truly inspired by God and it isn't just an a desire of one's own heart. It's a difficult thing to quantify for a few reasons. The first being it isn't on a metaphysical level that easy to determine what you as an individual actually is. The emotive complexity of a human spirit and holy spirit in the unity of a born again soul means it isn't entirely clear where you as an individual ends and God begins. Indeed the way this complexity manifests itself is entirely psychological which brings a certain lack of credibility to the entire theology, but at the same time it makes it entirely wonderful in its simplicity. I sometimes wonder if God designed it that way to drive those that spend their time obsessing over the validity of those that claim to know Christ insane, simply to reinforce that isn't really our job.
Of course one can say that the nature of the desire can be a good indicator, but that isn't necessarily the case. A missions trip to a spiritually barren destination may sound divinely inspired, or it may be just a desire to enjoy a holiday at a tropical destination.
From what I can tell the only way to be sure of the nature of one's desires is in hindsight. When one's only explanation is that God’s hand must have been in it, and that it was incredible, and miraculous that these events took place that. It must be divine intervention. It is His providence that is the proof of His calling.
A lot of the time when discussing these complex events we say God’s hands are in it. While I understand it as metaphorical I do often think it's the wrong metaphor. By the nature of the Holy Spirit being within us as born again Christians WE - the church - are God’s hands. We have to grip onto His callings with our will. The real miracles come not from metaphorical hands, but from metaphorical arms. We may grip onto His will but He does the heavy lifting. And when He flexes those divine biceps it really is wonderful to see.