Do New Testament Christians Need the Old Testament?

Ephesians Ephesians 2 Colossians Colossians 2 Hebrews Hebrews 1 Galatians Galatians 3 Acts Hebrews 2 Genesis Acts 7 2 Peter Genesis 1 Romans 2 Peter 1 1 Corinthians Romans 15 2 Chronicles 1 Corinthians 10 Joshua 2 Chronicles 16 2 Corinthians 2 Corinthians 3 Exodus Hebrews 11 Exodus 34 2 Corinthians 4