Sanctification also has an element of grace, because through sanctification which is based for the most part on works, is being guided by the Holy Spirit, this can be attested to by the writings of the Apostle Paul in Romans 8:26 -
Did you ever think that sometimes you are too weak to handle life's battles on your own?
Part of sanctification is manifested through prayer to our heavenly Father, so that we might persevere in all things according to His plan and will for our lives. God guarantees good as a result of doing what He asks. That is why, since we are in the flesh, and the flesh wars against us, we need assistance in every area of life, and that comes through the guidance of the Holy Spirit.
Grace (God's Love) is sufficient to cover our sins, but we have to be willing to not just observe grace, but to act upon that grace in order to be justifiable and glorified in Christ Jesus. As Christians we assess the present in the light of the future assurance of future happiness, as our love for God is evoked by knowledge of His love for us.
So, if someone has said that they are a "Christian," but when we look at their life and it doesn't model God's commandments, or Christ's example, are they still under grace?