Hebrews 9:8,14..According to this arrangement, gifts and sacrifices are offered that cannot perfect the conscience of the worshiper…14 how much more will the blood of Christ, who through the eternal Spirit offered himself without blemish to God, purify our conscience from dead works to serve the living God.

Every family or occupation has “works” we are to do in order to honor our parents or bosses expectations.  Though these responsibilities may get done, it’s possible that the parent or boss be pleased, yet we remain discouraged, ashamed or depressed, because doing outward “work” doesn’t promise inward peace to the “doer”…
The writer of Hebrews was trying to help these Jewish Christians realize the magnitude of what Christ purchased for them, in fulfilling all the religious duties in the Old Testament, for us to have peace and a clear conscience before God. (Matthew 5:17)  
In the Old Testament, religious works of the law were God’s expectations to honor Him, and He would mercifully bless Israel’s obedience in giving them lands, rains, agricultural abundance, protection, etc.  But through Christ, His blood would access us “better promises” of the Spirit which is life and peace inwardly (as well as outwardly). (Romans 8:6)
Even today, it is possible to do the religious act of forgiving, praising, and serving but not access the promises of God in having a clear conscience.  Because the Old Testament mentality looks to “work off debt” through religious works.  Whereas the true worshiper first takes all debts(sins) to “the cross”, to be cleansed of a guilty conscience to receive forgiveness and love.  So now that we have received love, that is what we owe others in whatever “work” that looks like…(Romans 4:4-5, Romans 13:8)
So if I need to forgive someone, I have a clear conscience before God equipped with His love to do so.  But until our conscience is clear before God, there is no “work” we can do to purify it.  There is no gift we can give, nor are there any words we can say, until we have dealt with honoring Christ blood first in humility through confession and cleansing.  
So keep striving to have a clear conscience before God, and people, so you can enjoy the fullness of Christ in salvation. (Acts 24:16)-In His Love, Ld