18 Wives, submit yourselves to your husbands, as is fitting in the Lord. 19 Husbands, love your wives and do not be harsh with them. (Colossians 3:18-19)
The Apostle Paul now provides wisdom for the family. This makes sense since the strength of any group, be it a church or a society, is dependent upon the strength of the family.
In any context there must be an authority structure, and there must be an order to that authority. Everyone plays a role in order for the goals to be accomplished. No role is less important than the next, they're just different roles and are necessary.
In v.18 God gives to the wife the role of supporting her husband. And, if the wife does not support her husband, recognizing his leadership role, there will be chaos in the home.
To the wife, God says, "submit to your husband." "Submit" means "to line up under someone." Of course, a husband who is fulfilling his God-given responsibility toward his wife will not have a wife who chooses not to submit to his leadership.
Now, it is not the husband's responsibility to make his wife submit. It must be voluntary, thus it is right in the sight of God.
Paul, in v.19, follows with a command to husbands. The husband is to love his wife. He uses the word "agape" which is the type of love which chooses to love with no ulterior motive in mind. This is an unconditional love which cannot be altered, even if the wife is not submitting.
Loving leadership is that which the godly husband wants to provide for his family. Of course, it is a product of all that the Apostle has been teaching us in all the verses before in the book. As with any relationship, the husband's love for his wife is most largely dependent on his walk with the Lord.
Not being harsh is a part of what loving one's wife looks like. Of course, resentment is of our flesh, our sinful desires, and often expresses itself in sarcasm toward our wives.
Women are wired differently than men. This is why Paul instructs the husband to resist criticism and sarcasm. These also are expressions of the flesh.