How do we know that we are truly sanctified by God?

Being sanctified by God involves understanding both God's eternal choosing and the immediate work of the Holy Spirit in our lives. Jude writes to those 'sanctified by God the Father, and preserved in Jesus Christ' (Jude 1). Sanctification is initiated by God's electing love from eternity, where He chooses believers to be set apart for Himself. It is also the work of the Holy Spirit, who indwells the believer and brings about spiritual transformation. The essence of this sanctification reflects God’s holiness and sets us apart to fulfill His purposes in our lives as we grow in faith and obedience.