The applications Paul provides the Church here at the conclusion of his letter to the churches in Galatia are both Spiritual and practical.
And he appeals to the practical as a means of explaining and encouraging the Body of Christ to know the Spiritual is every bit as real as the practical.
For example, (and employing an example,) Paul discusses the importance of investing fully in the kingdom of God. He uses the principle of sowing and reaping to help us to understand the importance of the kind and quality of the investments we make.
Some people may not think of themselves as investors, but everyone is an investor. We all have 24 hours of time every day. We all have a measure of physical strength and mental energy during the course of those 24 hours of time each day. We all have some measure of provision given to us by God available to us to employ, be it from great wealth or great poverty. There are no exceptions.
The illustration Paul provides is from agriculture because this is a largely agrarian society. But even us modern urban city types have enough life experience to know that the seed we put in the ground can only yield a plant – and then the fruit – of the kind of seed planted.
You will never get a potato from a grain of corn. It is guaranteed beforehand a corn plant will be the result of planting a grain of corn – and even more so when the corn seed planted is properly cared for – with water and sunlight, and weeding and protection from pests.
In the same way, you will never reap a Spiritual harvest from a physical investment.
When you sow to the Spirit you are GUARANTEED to reap a Spiritual harvest. How great is that news!
Also in the same way, the harvest you reap will also be much greater than the seed you sow. If you plant a single grain of corn, and especially when the corn seed is properly cared for, the harvest will be many-fold greater than the single seed planted.
God has designed it so investments in the agricultural kingdom produce a multitude of fruit as a means of feeding those who inhabit earth. In exactly the same way, God has designed it so those who invest in the kingdom of heaven will also reap a multitude of Spiritual fruit, both in this life – and in the next.
The problem, I suppose, is our investment in the kingdom of heaven is invisible. But it more than makes up for its invisibility by its eternality.
Nothing done for self will last, while everything done for God will both last eternally, and be multiplied exponentially. You can count on it.