Jesus Christ appeared to His apostles after His resurrection for forty days and taught them in detail about the kingdom of God(Acts1:1-3). Before His death He told them that the kingdom of God would come. After His death and resurrection He commanded them the things pertaining to that kingdom. And He showed and taught them the patterns. Here the kingdom of God means the church of God.
Jesus gave the commandments pertaining to the kingdom of God only after His resurrection. Confession and remission of sins are among them. On the day of His resurrection, at the evening, when the disciples were assembled in a closed room, Jesus came and stood in their midst and said to them, "Peace to you! As the Father has sent Me, I also send you". When He said this, He breathed on them and said to them, "Receive the Holy Spirit. If you forgive the sins of any, they are forgiven them; If you retain the sins of any, they are retained" (John 20:21-23). This is the first commandment and authority, which Jesus gave to His disciples. Here the authority is granted to the disciples to forgive those sins, which are confessed by others. The Lord has declared that those sins, which are yet to be confessed, will not be forgiven. The book of James conforms to this principle.
It is written, "Is any one among you suffering? Let him pray. Is anyone cheerful? Let his sing psalms. Is anyone among you sick? Let him call for the elders of the church, and let them pray over him, anointing him with oil in the name of the Lord. And the prayer of faith will save the sick, and the Lord will raise him up. And if he has committed sins, he will be forgiven. Confess your trespasses to one another, and pray for one another, that you may be healed. The effective fervent prayer of a righteous man avails much (James 5:13-16). The epistles of the New Testament are written for the believers. When fallen sick, a believer would have certainly humbled himself and prayed to the Lord. However the Scriptures advise to call for the elders of the church! When a believer falls sick, only the minister of God should come and pray. Not assuming that visiting him is the duty of the minister, he should arrange to call for the minister. To be healed, he should confess his sins before the minister. Then the minister should anoint him with oil in the name of the Lord and pray for him. The Lord will heal him and according to Ap.James, his sins would be forgiven.
The verse 'confess your trespasses to one another' does not mean that believers should confess their sins to each other. A believer should confess his sins only to a minister. In the next verse, the Holy Spirit has mentioned the name of a minister of God. "Elijah was a man with a nature like ours, and he prayed earnestly that it would not rain, and it did not rain on the land for three years and six months. And he prayed again, and the heaven gave rain, and the earth produced its fruit" (James 5:17,18). The effective fervent prayer of a righteous man avails much (James 5:16). It is not the confession of one sinner to another or a confession of one believer to another believer. "We know that God does not hear sinners; but if anyone is a worshipper of God and does His will, He hears him" (John 9:31).
Are you saying that all are sinners and therefore a sinner should not confess to another sinner (man)? We are justified freely by His grace through the redemption that comes by Christ Jesus (Rom.3: 24). "Since we have been justified through faith, we have peace with God through our Lord Jesus Christ" (Rom.5: 1). "He was delivered over to death for our sins and was raised to life for our justification" (Rom.4: 25). The Scripture foresaw that God would justify the Gentiles by faith (Gal.3:8). When the believers so justified commit sin and fall sick, they should confess their sins before the minister of God, and then God forgives their sins and heals them. This is the method prescribed by the church.
Even from psychological point of view, it is an established fact that when a man shares his burdens, worries and errors openly with another, he is relieved of his mental burden and receives peace and comfort. Therefore you should confess your sins to a just minister of God in order to receive divine healing and for your material and spiritual well being. Make reconciliation with those whom you have to and correct yourself wherever needed. The Lord shall raise you. Your sins will be forgiven. So say the Scriptures. May those who want to be healed do likewise!
"And he looks at men and says, 'I have sinned'" (Job 33:26,27)