The Concept of Justification and Sanctification actually came from the Old Covenant and was completed by the New Covenant.
The system of atonement had always existed. Even in the OT, no one can walk perfectly in God's Laws, and hence no one are eligible to enter into God's Kingdom without having a sacrifice to atone for sins. That is Justification by works, which is meant to pardon Israelites who trespasses God's holy Laws, to keep them from the wages of Sin. But Justification is not meant for those who take God's laws for granted... sinning willfully just to get pardoned. The prophets has warned Israel many times about this. Justification (pardon) is meant for those who WANTS TO obey God, but unable to do so perfectly.
Sanctification is holy living. The Law of God did not appear only at Sinai. Before Exodus; Cain, Sodom and Gomorrah was judged by the very same standards which the Law of God demands. Salvation was actually offered to Israel in Exodus 19 in the condition that they obey God's Laws. That is actually Sanctification ( Holy Living). If one who follows God's Commandment, makes a mistake and violates it, he is given a chance to atone for his sins by animal sacrifice; Justification, which is pardon from punishment.
The mode of Justification in the NT has been replaced by Christ who is our perfect high preist and lamb. The mode of Sanctification remains the same, obedience to the Law of God which is also called the word, truth, commandments, voice, etc.
That is called Justification by Faith.