Pastors, by definition, are generalists. We are supposed to be specialists in the Bible, but the Bible is so broad in its scope, a teacher of the Bible must be a generalist. A good pastor is one of the last generalists left in our highly specialized society.
The Bible teaches on marriage, sex, parenting, money, work, civil government, business, banking, international relations, how the world came to be (which touches on science), education, history, relationships, communication, mental and emotional health (psychology), physical health, immigration, masculinity and femininity, stewardship, justice, history, friendship, art and beauty, music, care for the poor, and so on.
No preacher who preaches the whole counsel of God will preach “just the gospel.” He will inevitably find himself speaking to virtually every area of life because Scripture does. When people tell pastors, “stay in your lane,” meaning pastors should stick to things that are considered “spiritual,” they are actually trying to muzzle the Bible. They are operating in liberalism’s frame, which privatizes religion. A faithful pastor will not allow the Bible to be compartmentalized. A faithful preacher will inevitably reject liberalism’s commitment to a religiously neutral public square. A faithful pastor will seek to teach the Bible in such a way that he equips his people for EVERY good work, which is to say, good works in EVERY area of life.
Specialization is for insects, not for pastors.
ADDENDUM: Most pastors today lack the classical education that used to be presupposed. Seminary education is extremely narrow today and focused as much on managerialism as theology, history, etc. Most seminaries do not provide any political theology. Etc.
And yes, all men should strive to be generalists in a certain sense – and not just in academic fields but practical ones as well. Every man should seek to be a human Swiss Army knife.
ADDENDUM: I’ll give you an example of what I have in mind:
If a pastor is preaching through 1 Timothy 4, when he gets to verse 8, it would be perfectly appropriate to point out that if bodily training is of “some value,” Christians should treat it as such in their lives. Don’t obsess over health, but be a good steward of it. Train your body to maximize your usefulness. Develop your physical potential. Take care of your body. Etc.
But he would not need to prescribe a specific exercise routine or weight lifting regiment. Leave that to the specialists in this area.
Another example: When the pastor is preaching through Titus 2, he can talk about the kinds is skills women need to develop to be “homemakers” or “workers at home.” Wives and mothers are anchored to the domestic sphere and should glorify it. They should manage their homes in an orderly way. To do so honors God and prevents his Word from being blasphemed. Cooking, cleaning, and maintaining the household, serving husband and children are noble tasks.
But he does not need to tell the women the finer points of how to iron a shirt or fold bedsheets or bake the perfect apple pie.
Generalists, in the nature of the case, deal with the big picture.
When a pastor preaches Romans 13, he should lay out the magistrates God-ordained duties to protect the righteous and be a terror to evil doers. He can explain the difference between a sin and a crime. He can lay out the Bible’s political theology and the proper functions of the state. He can point ways in which the civil order where he and his congregation live violates God purpose for civil government. He can compare party platforms to what the Bible says on various issues. He can even call magistrates to repentance for ways they misuse their office, failure to administer God’s justice, etc.
But the pastor does need to comment on every piece or legislation that comes up for a vote. He doesn’t need to involve the pulpit every political topic that comes up in the news cycle.