Sanctification is strictly through using Christ who is both Lord and Savior. Since Jesus’ death has rendered the law ineffective (in Him alone Jesus’ Lordship in one’s life becomes the guide since in this case the guide is a living Person) the law is useless as a guide because Jesus’ death has rendered it both fulfilled in His death and now set aside for living as a disciple both dead to sin and alive to God in Jesus Christ, as St. Paul writes.
How is Jesus' lordship manifested in believers' lives? I think Jesus gives us a hint.
John 14:15: "If you love me, you will keep my commandments."
John 14:21: "Whoever has my commandments and keeps them loves me. Whoever loves me will be loved by my Father, and I will love them and reveal myself to them."
John 15:10: "If you keep my commandments, you will remain in my love, just as I kept my Father’s commandments and remain in his love."
John 15:14: "You are my friends if you do what I command you."
John 15:17: "I give you these commandments so that you can love each other."