In the massive virtual reality games run over the internet at this beginning of the 21st Century, a player deals with thousands of other players from around the world -- and with the game's administrators. Administrators can change the environment by, for example, introducing disease into the virtual world. (See "Playing With Epidemics", Science magazine, 18 May 2007, page 961.)
In the actual reality game, we have the Holy Spirit.
In actual reality we have the privilege of working in concert with the Spirit. First, the Holy Spirit has laid out the game's premises fairly transparently and provides the means by which we players, if we work together diligently, can discover the details of how the game works -- how real diseases arise and propagate, for example. In this way, the players can conform our actions to the actual reality of the world and thereby have much greater effects than we could otherwise. We can float logs downstream instead of hauling them over hill and dale.
Second, the Holy Spirit is eager to communicate individually with each player. I don't say that we can automatically obtain whatever information we ask for, but that we are offered specific information which is pertinent for living in concert with the direction of the overall game.
The Spirit may say to one person, "Hey, the progress of the world would really be better if you'd serve the meal at my table." This person, if responding affirmatively, would then become a minister of God. (This is traditionally described as a "call", and in fact some people only recognize this particular message under the heading of "call".) To become a minister at God's table often means adopting a professional occupation (the "ordained clergy") but there are also ministers who are not professional clergy, who serve the meal only to narrower subsets of the people, such as those physically unable to come to the table.
Or perhaps there is a farm worker up in Door County whose primary occupation is taking care of the animals and helping to prune the cherry trees. Suppose the Spirit said to this person, "I need someone to go down to the capitol in Madison and explain what I want done." This farmhand would then have been called to become a prophet.
Other people, not all farmhands, not all from Door County, and not all of them sent by God, will also speak at the capitol in Madison about what should be done. But they are not properly called prophets. That term is reserved for those stating the words of the Spirit.
A third example: Some people become teachers. There are people who have a full-time occupation working in schools with the formal title of teacher, there are teachers who work a few hours a week in the church schools, there are volunteer tutors, and there are those who travel to distant places to commit all of their time to teaching. Some teach through letters and conversations at opportune moments with no formal plan at all. Many of these people are called by the Spirit to take on the role of teacher. Others take on the role because they enjoy being in schools, or because they don't function well in most other settings, and some take the job because someone other than the Spirit asked them to do so.
In this comment, I am pointing only to those cases where the Administrator of the actual reality game speaks, calls, suggests, commands some individual to perform some particular role or task, and that individual accepts the call to function in concert with the Spirit to make a better game. These are the cases where the game's administrator knows the flow of the river and guides some of us to use that knowledge to move the timber more quickly, more easily, or - most importantly - to a more suitable destination.
The person who hears and heeds the urging of the actual reality game's Administrator will not have complete knowledge of the game, may not even be familiar with the destination, but nevertheless is permitted to assist in improving the game and the actual lives of the players in it.