A good friend received a challenge from a hyper-Wesleyan of sorts. The person argued that "no where does the Bible claim justification covers sins committed in the future." I beg to differ.
For by one offering He has perfected for all time those who are sanctified - Hebrews 10:14
Justification is a zero-tolerance issue. We must keep a fresh stock of verses to tear down any lofty thought which sets itself against this glorious doctrine.