Jesus gave the Church the authority to forgive sins

Lutero:

In order to gain forgiveness for sin, God teaches that we must admit our wrongs to Him, not a Roman Catholic priest.

Show me from Scripture. Because what I see, is that Jesus gave the Church the authority to forgive sins:

John 20:23

King James Version (KJV)
²³ Whose soever sins ye remit, they are remitted unto them; and whose soever sins ye retain, they are retained.

Roman Catholic priests do not represent Christ in any way,

Perhaps Protestant ministers don't. But Catholic Priests, in fact every Catholic does:
2 Corinthians 5:20

King James Version (KJV)
²⁰ Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ's stead, be ye reconciled to God.

Any Catholic or former Catholic can see in that verse, a reference to the Sacrament of Reconciliation.

a Roman Catholic priest can only represent himself as a minister of the religious cult he believes in, swears his alliegence to, and thus affliates himself with.

It is Protestants who represent a cult. Their coming was forecast in Scripture:

2 Timothy 4:3

King James Version (KJV)
³ For the time will come when they will not endure sound doctrine; but after their own lusts shall they heap to themselves teachers, having itching ears;

"If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness" (I John 1:9).

 Again, that is another reference to the Sacrament of Confession.

Once again, the confession of sin is to God

 Through the Church.  Scripture says:

James 5:16

King James Version (KJV)
¹⁶ Confess your faults one to another, and pray one for another, that ye may be healed. The effectual fervent prayer of a righteous man availeth much.

because it is God whom we offended, thus only God can release ("forgive") us of our debt due to our sin.

God will forgive your sins if you ask His beloved Priests to pray for you as God forgave Job's friends only after Job prayed for them:

Job 42:7-9

King James Version (KJV)
⁷ And it was so, that after the Lord had spoken these words unto Job, the Lord said to Eliphaz the Temanite, My wrath is kindled against thee, and against thy two friends: for ye have not spoken of me the thing that is right, as my servant Job hath.
⁸ Therefore take unto you now seven bullocks and seven rams, and go to my servant Job, and offer up for yourselves a burnt offering; and my servant Job shall pray for you: for him will I accept: lest I deal with you after your folly, in that ye have not spoken of me the thing which is right, like my servant Job.
⁹ So Eliphaz the Temanite and Bildad the Shuhite and Zophar the Naamathite went, and did according as the Lord commanded them: the Lord also accepted Job.

Christians don't have a mediator between themselves and God.

Really?1 Timothy 2:5

King James Version (KJV)
⁵ For there is one God, and one mediator between God and men, the man Christ Jesus;

Every true Christian is a priest and has the right to approach God directly.

And every true Christian has advocates to God in the Body of Christ:

1 Timothy 2:1

King James Version (KJV)
1 I exhort therefore, that, first of all, supplications, prayers, intercessions, and giving of thanks, be made for all men;

Even the Apostles were humble enough to request their congregations to be advocates in their behalf:

1 Thessalonians 5:25

King James Version (KJV)
²⁵ Brethren, pray for us.

"You also, as living stones, are being built up a spiritual house, a holy priesthood, to offer up spiritual sacrifices acceptable to God through Jesus Christ" (I Peter 2:5).  Spiritual Sacrifices? What are those?

Alms. 

Luke 11:41

King James Version (KJV)
⁴¹ But rather give alms of such things as ye have; and, behold, all things are clean unto you.

Physical sufferings:

Colossians 1:24

King James Version (KJV)
²⁴ Who now rejoice in my sufferings for you, and fill up that which is behind of the afflictions of Christ in my flesh for his body's sake, which is the church:

Charity:


Mark 10:21

King James Version (KJV)
²¹ Then Jesus beholding him loved him, and said unto him, One thing thou lackest: go thy way, sell whatsoever thou hast, and give to the poor, and thou shalt have treasure in heaven: and come, take up the cross, and follow me.

Sincerely,

De Maria