Nature and Scripture represent two means to the same end: knowing God. The first (nature) has limits in that it can tell us the invisible things of God but only leave us without excuse. Scripture alone can savingly come to us since we must hear the preaching of the word and believe by faith.
“For no one ever hated his own flesh, but nourishes and cherishes it,” reasons Paul before saying, “just as Christ does the church, because we are members of his body” (Eph 5:29–30).
Paul here moves seamlessly from the nature of human bodies to the supernatural grace of Christ’s for the church. Paul then continues moving from nature to grace by defining the church as those who are “members of his body.” By members, Paul means parts of the body: a hand, a foot, an eye, and so on.
Nature explains grace. That’s why God made everything.
Study the ant and you will “be wise (Prob 6:6). Study also agriculture, zoology, and cosmology to grasp the resurrection. These concrete arts make sense of a great mystery of faith. If we do not, then might fall under the rhetorical flourish of Paul’s “foolish person” in 1 Corinthians 15:35.
In this passage, he explains: What you sow does not come to life unless it dies. And what you sow is not the body that is to be, but a bare kernel, perhaps of wheat or of some other grain.” (1 Cor 15:36–37). Yet agriculture does not alone give a concrete understanding of the resurrection.
Paul also uses zoology and cosmology to make sense of our resurrection body. He writes:
38 But God gives it a body as he has chosen, and to each kind of seed its own body. 39 For not all flesh is the same, but there is one kind for humans, another for animals, another for birds, and another for fish. 40 There are heavenly bodies and earthly bodies, but the glory of the heavenly is of one kind, and the glory of the earthly is of another. 41 There is one glory of the sun, and another glory of the moon, and another glory of the stars; for star differs from star in glory (1 Cor 15:38–41).
Study animals. Study the night sky. Grasp the sort of things they tell us about the one who made them! Here, Paul tells us of the varying glory of the cosmos which itself declares “ the glory of God and the sky above proclaims his handiwork” (Ps 19:1). Here, Paul uses these natural analogues to make sense of the glory of the human body: “It is sown a natural body; it is raised a spiritual body” (1 Cor 15:44).
Nothing about this should surprise us. God created marriage (Gen 2:24) to signify Christ’s union with the church, his body. After citing Genesis 2:24, Paul writes: “This mystery is profound, and I am saying that it refers to Christ and the church.”