2 Thessalonians 1:1 Paul, and Silvanus, and Timotheus, unto the church of the Thessalonians in God our Father and the Lord Jesus Christ: 2 Grace unto you, and peace, from God our Father and the Lord Jesus Christ. 3 We are bound to thank God always for you, brethren, as it is meet, because that your faith groweth exceedingly, and the charity of every one of you all toward each other aboundeth; 4 So that we ourselves glory in you in the churches of God for your patience and faith in all your persecutions and tribulations that ye endure: 5 Which is a manifest token of the righteous judgment of God, that ye may be counted worthy of the kingdom of God, for which ye also suffer: 6 Seeing it is a righteous thing with God to recompense tribulation to them that trouble you; 7 And to you who are troubled rest with us, when the Lord Jesus shall be revealed from heaven with his mighty angels, 8 In flaming fire taking vengeance on them that know not God, and that obey not the gospel of our Lord Jesus Christ: 9 Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power; 10 When he shall come to be glorified in his saints, and to be admired in all them that believe (because our testimony among you was believed) in that day.
This is one long, complicated sentence. The conclusion is that Jesus Christ will be glorified in His saints when He comes.
The reason He is glorified in the saints is because they were patient in persecutions and tribulations as they witnessed concerning the Lord. They didn't become bitter, didn't lash out, their love towards others abounded. The fact that they were enduring these persecutions was a token that others could see of God's righteous judgment that we may be counted worthy of the kingdom of God. I don't know if I have ever heard this taught in Christianity. We focus on Jesus Christ being worthy, and that we stand on His blood. Both of those things are true. However, "standing on HIs blood" while patiently enduring trials, tribulations and persecutions so that you might be counted worthy, that is a very different perspective. This explains what the Lord shared in Matthew 18. He forgave this man of all his sins, but then he went out and would not forgive someone who had sinned against him. The Lord told him that since his debt had been forgiven by the Lord he also should have forgiven the person who sinned against him. So yes, our sins have been forgiven by the Lord, that is our only standing, but it should also result in our response, patiently enduring persecutions where people sin against us, and our enduring these things is a manifest token of God's righteous judgement. We understand that at the end of the age the Lord will be manifested with His angels, taking vengeance on those that know not God and don't obey the gospel. That is why we are patient, enduring trials and tribulations, built up in the faith, abounding in love, so that we might, if possible, pull some out into salvation.
For example, I heard this testimony this past Lord's day about twelve teachers who were killed by Islamic soldiers in some country in Africa, I think it was Ghana. The leader of the teachers prayed for the soldiers who were about to kill them knowing that they were about to do something horrible and would be wracked with guilt. So he prayed that someone would come to them and share the gospel of the Lord's forgiveness so that they could be saved. The teachers then sang a hymn about how they were coming to the Lord. Afterwards the leader of these soldiers was wracked with guilt, sought out someone who could share the gospel with him, got saved and shared this story.