There is a lot of great symbolism in the church. For example, baptism reveals a life that is changed. It is buried in the water to be raised to a new life. The Lord's Supper represents the broken body of Christ and the blood that was sacrificed so that we might have forgiveness. These are wonderful symbols of our faith which we should keep dear to us.
However, making anything symbolic sacerdotal adds to the gospel. Anything that adds to the gospel is departing from the gospel.
The gospel is a gift of faith. We believe as we receive the faith God grants us for salvation. We do not need to work for our faith. It is a gift. We receive this faith and we are saved. Adding to the gospel is saying that the sacrifice of Jesus on the cross would not satisfy the requirement for forgiveness.
I some times see people unconsciously adding to the gospel. They somehow believe their "big monetary gift" to the church will give them salvation. They think that their painting of the church buildings will usher them into heaven. Now, I am not saying that there aren't rewards for obedience to the Lord. I am simply saying that those things have nothing to do with salvation. They are a result of a continued faithful life.
I heard a famous country-western singer singing Amazing Grace as an add for the tv show, "Lost"the other night. While the song is definitely taken out of context, I thought of that singer. I thought that God saves people not based upon their goodness but upon the faith that singer can (or has, I really don't know) receive from Him. I thought about how really amazing grace is.
Don't let people add to the gospel. Don't fall into the trap of having to work to "prove" your faith when that proving is actually being preached as "obtaining" the faith. It is God's gift. One in which we should say "thank you" to God with the lives we live.
Amazing Grace, how sweet the sound,
That saved a wretch like me.
I once was lost, but now I'm found,
Was blind but now I see.
Galatians 1:6-7 (ESV)
6 I am astonished that you are so quickly deserting him who called you in the grace of Christ and are turning to a different gospel—7 not that there is another one, but there are some who trouble you and want to distort the gospel of Christ.