Over the years and from various corners, I have heard this bit of proverbial wisdom:
"You should only go into the ordained ministry if you can't imagine yourself doing anything else."
I think that this is an unhealthy perspective to maintain. If you are an ordained minister or are otherwise working full-time in lay ministry, there will be days in your life when you can easily imagine yourself doing something else. I have certainly had days in the past year of my first pastorate when I have looked upon my former career as a librarian with fondness, if not envy.
To expect that every day in ministry will be so filled with elation that the minister cannot imagine doing anything else is an unrealistic and unachievable standard for happiness. For that matter, it's not even Biblical. Take, for example, the ministry of Elijah. He was a faithful prophet who proclaimed the Word of God to kings and empires. But even in the wake of tremendous victory, he could feel despair of God's call on his life:
But he himself went a day’s journey into the wilderness, and came and sat down under a solitary broom tree. He asked that he might die: ‘It is enough; now, O Lord, take away my life, for I am no better than my ancestors.’ (1 Kin 19:4 NRSV)
Jeremiah likewise expressed misery in his own ministry in the final days of Judah’s independence. He even went so far as to question God’s integrity in calling him:
Why is my pain unceasing, my wound incurable, refusing to be healed? Truly, you are to me like a deceitful brook, like waters that fail. (Jer 15:18 NRSV)
Hosea was ordered to marry a prostitute. Jonah physically fled from his call. Surely these ministers had days in which they could imagine doing some other line of work than ministry! Shall we, then, hold ourselves to be greater than the prophets of the Lord?
Those of us who serve in full-time ministry or are preparing to do not do so because we find it blissful.
We do so because we are called.