Paul makes clear in this passage that we are responsible for setting our minds on the things of the Spirit. In other words, we have to exercise our minds. We are not to be passive, waiting for something to happen to us. God expects us to use our faculties and engage in mental effort through his strength. None of us can say that we cannot do this. If we believe in Jesus, the Spirit is at work within us secretly to bring this about clearly in our thoughts. What is it like to think as a Christian? Here are some suggestions.
First, a Christian will think about spiritual things instinctively. By this, I mean that he does not find it an unusual activity. What does a football supporter think about instinctively? He will think about his team. Who does a parent think about instinctively? A father or mother will think about their children and how to care for them. What country in the world does a person think about instinctively? He or she will think about their homeland. In a far higher sense, a Christian will think about the things of the Spirit. If he or she does not do so, there is something wrong with them spiritually.
Second, a Christian will think about the things of the Spirit progressively. Christians grow in understanding of the things of God gradually, and such growth will happen. All Christians will grow in grace, although not at the same rate.
Third, a Christian will think about the things of the Spirit appropriately, in ways that are suitable and relevant to his current situation. If he has sinned, he will think of God’s forgiveness; if he is under temptation, he will think of God’s help; if he is facing choices, he will think of God’s promises of guidance; if he is going through difficult providences, he will think of God’s wisdom and power. In times of joy he will recall the goodness of God; if he is facing turmoil, he will think of the peace that God has to give. There are many ways of thinking appropriately about the things of the Spirit.
Fourth, a Christian will be pleased with the things of the Spirit. He will not be satisfied entirely with his progress because he is aware that he has to continue in thinking about them. Yet he is glad to discover that he has a delight in and a longing to focus on them. Once he has tasted them he does not desire the taste of anything inferior. He discovers that the things of the Spirit are comforting and challenging, plentiful and personal, ideally meeting the needs of his or her soul.