I’m not sure this talk of vocations makes sense outside of a Catholic context. Do Protestant and other denominations have the concept of "vocation?" How can we explain it to those who don’t?
I suppose we start from Heaven and work backwards.
Heaven is like a wedding feast. Cf. Hosea. Cf. the book of Revelation. Cf. several parables.
The Church is the Bride of Christ. So all of us here in the Church—men and women—are getting ready to be united to Him as his Bride.
Working backwards, here on Earth. We are stained with original sin, so the following doesn’t work out for every individual as perfectly as it should. But in the original plan, we’re supposed to get ready for the marriage of the Lamb by committing our whole self to a marriage consecration, or a marriage-like consecration, one that requires the gift of our whole person.
A nuptial commitment.
A commitment that is grounded in promises that we are bound to keep.
The marriage of the Lamb is eternal. Timeless. Here on earth we deal in time, so instead we say that the promises are permanent.
So each one of us is ordered toward a permanently vowed life.
Marriage is an example of a permanently vowed life.
We Catholics understand two other major kinds of permanently vowed lives: the life of a vowed celibate, and the life of a priest.
God calls every one of us to one of these vows.
God calls every one of us, in this life, to take the step of committing our whole selves, with Him, in a real, nuptial relationship; or, to Him, through a nuptial relationship with a spouse.
We do this by vowing our whole selves, holding nothing back.
In particular, we commit to God all our sexuality: either in service to marriage, or in service to celibacy, laying it on the altar before God as a "holy and living sacrifice."
In particular, we commit to God all our physical and mental labor: in service to a family, or in service to all families, through pastoral care or through prayer.
We do this in response to His call: in response to our vocation.
No job is a vocation, although a job can be part of our response to our vocation.
No career is a vocation, although a career and preparation for it can be part of our response to our vocation.
Some of us, even though we try, don’t reach the point of professing vows. Perhaps we are called to marriage but we never meet a suitable mate. Perhaps we are called to the priesthood but some handicap or obstacle keeps us out of seminary. Perhaps we are called to the religious life but can find no convent, no order, into which we can fit. Perhaps we simply don’t live long enough to bring our response to fruition. All this is a result of sin.
But the vocation is still there.
Our vocation demands everything from us. Because God demands everything from us. In the end, we give him everything, or we give him nothing.
If you still do not know your vocation: listen, listen, pray and listen.
If you are aware of your vocation but have not brought it to fruition: prepare, pray, seek—seek the spouse God has called for you, seek the order whose vows you will profess.
If you already live in your vocation, ask yourself this: How can I turn over everything I have and everything I am in service to my marriage, or to my priesthood, or to my lifelong consecration?
Turn it over to the service of your vocation and you turn it over to God.