sanctification IS a one time event at the same time as we are justified. All it means is when we are cleansed, we are set apart for righteousness. But being set apart is not a life-long process. Becoming like Christ in ALL attributes besides sinlessness IS a life-long process called glorification. It is the maturing of the fruit of the Spirit.
YOu don't even know the word of god nor the Spirit of God.
Sanctification is both a one time event and an ongoing process. but if you were even a casual student of the word, you would have learned that.
Hebrews 10:14
For by one offering he hath perfected for ever them that are sanctified.
Sanctified here is in the present (not past) passive participle in the accusative case.
Now because you don't appear to wish to study to show yourself approved let me show you what that means:
Present- statement of facct actually occuring in real time
Passive- the person spoken of is the recipient of the action
Participle having an ending in "ed" (if past) or "ing" if in the present or future.
So what God said here is- He has finished forever, those who are being made holy!
In other words oh pharisee- God declares us perfect because of the blood of Jesus, then gives us the Holy Spirit and begins the process of making us holy that goes on till we go home to be with Him.
Thus endeth the lesson and thus should end the false belief you were taught!