This is from Every Good Endeavor by Tim Keller:
"Paul uses these same two words [calling and assigning] here when he says that every Christian should remain in the work God has “assigned to him, and to which God has called him.” Yet Paul is not referring in this case to church ministries, but to common social and economic tasks—“ secular jobs,” we might say— and naming them God’s callings and assignments. The implication is clear: Just as God equips Christians for building up the Body of Christ, so he also equips all people with talents and gifts for various kinds of work, for the purpose of building up the human community."
"Our daily work can be a calling only if it is reconceived as God’s assignment to serve others."
"We are not to choose jobs and conduct our work to fulfill ourselves and accrue power, for being called by God to do something is empowering enough. We are to see work as a way of service to God and our neighbor, and so we should both choose and conduct our work in accordance with that purpose. The question regarding our choice of work is no longer “What will make me the most money and give me the most status?” The question must now be “How, with my existing abilities and opportunities, can I be of greatest service to other people, knowing what I do of God’s will and of human need?”
"If the point of work is to serve and exalt ourselves, then our work inevitably becomes less about the work and more about us. Our aggressiveness will eventually become abuse, our drive will become burnout, and our self-sufficiency will become self-loathing. But if the purpose of work is to serve and exalt something beyond ourselves, then we actually have a better reason to deploy our talent, ambition, and entrepreneurial vigor— and we are more likely to be successful in the long run, even by the world’s definition."
Keller, Timothy (2012-11-13). Every Good Endeavor: Connecting Your Work to God's Work (pp. 65-68). Dutton Adult. Kindle Edition.