Final answer:
The statement that sanctification's core concept in the New Testament is holiness is true. Sanctification involves becoming holy and is closely linked with the idea of being set apart or consecrated to God.
Step-by-step explanation:
The assertion that the root concept for the New Testament idea of sanctification is holiness is true. The term sanctification comes from the Latin word 'sanctificare' which means to make holy. In a theological context, particularly within Christian doctrine, sanctification is the process of becoming holy, set apart, or consecrated to God. In the New Testament, this process involves the transformation and renewal of an individual through the work of the Holy Spirit to conform to the image of Christ.