It seems that a good number of people who are not Christians see the Bible as a rulebook for life. That it is a set of moral codes and ethics which need to be adhered to in order to be Christian. For defending the Christian faith, Christians need to help people get beyond this view of what the Bible is and what being a Christian is.
The Bible is not a rule book. It is a love letter from God to us.
Christianity is not a way of life - it is life!
For clarification I have copied the following from a written manuscript by my high school's retired congregational pastor, entitled "Christianity 101":
The Bible: God’s Love Letter – not a secret code book; a living Word, not dead letter.
a. Old Testament -- 39 books
i. The Canon or Pentateuch (5 books): Genesis – Deuteronomy
1. Message: God created the world, sin entered, God began a plan to save the world through a Savior to be born.
ii. His-story books (12 books): Joshua-Esther
1. Message: Humans cannot save ourselves. Kingdoms come and go – so do wars and sin.
iii. Poetic books: Job, Psalms, Proverbs, Ecclesiastes, Song of Solomon (5 books)
1. Message: God loves us.
iv. Minor Prophetic books (17 books): Isaiah-Malachi
1. Message: Turn (repent) or Burn (live in sin). The Savior is coming.
b. New Testament -- 27 books
i. Gospels (4 books): Matthew-John
1. Message: It’s all about Jesus. All four biographies about Jesus.
ii. HIS-story (1 book): Acts of the Apostles
1. Message: How the Christian Church was born (after Jesus’ resurrection) & spread.
iii. Letters (21 books): Romans-Jude
1. Message: Letters written to real churches, cities, people about living as Jesus’ disciples.
iv. Victory book (1 book): Revelation
1. Jesus comes again – Judgment – Those who trust in Jesus as Lord and Savior are saved and will live together forever with God in Heaven with resurrected bodies and recognition of
each other, all glorifying and worshiping the Lord Jesus.
I believe that clarifying more specifically what the message of the Bible actually is and what Christianity is will go along way in leading people to a relationship with Jesus Christ.