I do not believe anyone would question that people are called to Christian ministry, but does it also apply to secular occupations?
First of all, why do people work? Well, of course, the obvious answer is that it provides the necessary remuneration to support a family and pay the bills. However, does it go beyond that? Some Christians believe that God puts people into a particular occupation or job at a specific time and place for a reason. I am not going to dispute that! That is true in some cases. I believe that my present job serves more of a purpose than simply providing income, but do I believe I have been called to it? No, I do not.
Before going any further it is necessary to understand the concept of being called. It is a word used very flippantly by many Christians as a part of religious jargon, but the word must never be used casually, because to be called, in God's eyes, is a very serious matter. The word "calling" is overused and misunderstood.
I have posted several article on faithwriters dealing with this subject so I am not going into great detail again. Suffice it to say, if you are called you will have a passion or sense of urgency to do something, and a restlessness if you don't. You will see opportunities open up to use your spiritual giftedness. A calling will be confirmed by other people and have God's blessing upon it.
How does this all apply to secular work, or does it? I have a job that enables me to earn money, and I HAVE to show up for work if I want to get a pay check. I also have a writing and speaking ministry which I do even if I never make a dime because it is my calling, and I love it!
God has called many people down through history for specific purposes. Samuel had a distinctive, audible calling to be a prophet in I Samuel 3. There is an interesting account recorded in Exodus 31. Here, God specifically called Bezalel to make things for the tabernacle and the ark of the covenant. Read verses 2-11. However, in both cases and many others throughout the Bible, God gave the requirements and skills necessary to fulfill the calling, and both were related to some type of ministry.
I am not aware of any scriptural basis to support God calling people to be plumbers, carpenters, teachers, or whatever, just for the sake of earning a living and not related to ministry. There are, however, people who go into a secular occupation because they have a passion for it, they are good at it, and they love what they do. This does not mean they have a spiritual calling of God to do it.
Hopefully, you are engaged in a profession or job that you enjoy, using your abilities and talent, but that doesn't mean you were called to do that. YOU chose to do what you are doing. In a calling, GOD chooses you to do something. Be very careful to distinquish between doing something simply because you enjoy it and are good at it, and a confirmed calling of God upon your life. I recently heard a man on a radio program talk about a person who asked him whether or not he should become a pastor or go into a secular line of work. This man's answer was very helpful. He said if a person has to ask that question then they should not become a pastor. This would apply to any Christian ministry. Of course, there are many people like myself, who have both a secular job and a ministry.
If you have a secular vocation you are doing it basically to earn a living. If you have a ministry you are doing it to build lives for the kingdom of God, using your spirit-manifested gifts in a specific ministry.