It allows every vocation to bring glory to God, work to be worship, and life to be religion. He is Sovereign Lord of all. In the beginning God spoke the Word or Logos Jesus Christ and creation was formed. Creation structure bears the fingerprints of God. Because there is order in creation, creation can be known.
Textbooks based on creational revelation do that.
The Bible's focus is on God, not people. The Bible is to be studied in its entirety, rather than limiting its relevance to certain portions of the New Testament. Francis Schaeffer stated that the omission of the first three chapters of the Bible would decimate his understanding of the world and his place in it. The Bible is also to be read contextually, rather than in a proof-texting manner. Scripture must interpret Scripture.