The priests are in mourning, those who minister before the Lord (Joel 1:9b).
The first requirement of being used by God in the life of others is to mourn on their behalf. We must identify with the pain and the suffering of that person. Each of us must be broken for others first.
In order to be fully used by God in the marketplace we need to understand what breaks the heart of God. When we understand what breaks the heart of God we are able to mourn on behalf of that person, or nation we are called to serve. What is it that breaks the heart of God? When we begin to answer this question we begin the first step to becoming instruments of change for those things that are important to God. Perhaps it is an overemphasis in our own talent and abilities, or lack of complete trust in Jesus. Perhaps it is the lack of respect for human life that leads to the killing of innocent babies. Perhaps it is the deceit and pride that often rules the marketplace of commerce. Or perhaps it is the strife and divisions among His own body that grieves Him most. When we begin to mourn over our own sins in these areas God begins to use us as instruments of righteousness to affect these things. It was only when God let me see my own sins in the marketplace and how they broke His heart that I began to be an instrument for His purposes.
Today, ask God to show you what things are breaking His heart that are a part of your world that He might want you to be the priest to affect for Him. The first step is identification with what breaks God's heart.