Being spiritually useful and productive glorifies the name of our Lord Jesus in us. Not only that, we are glorified in him.
Paul actually prayed that for the Thessalonians and us.
To this end, we always pray for you, that our God will count you worthy of His calling, and that He will powerfully fulfill your every good desire and work of faith, so that the name of our Lord Jesus will be glorified in you, and you in Him, according to the grace of our God and of the Lord Jesus Christ. 2 Thessalonians 1:11-12
He tells us he prayed that prayer because they were being spiritually useful.
Paul, Silvanus, and Timothy, To the church of the Thessalonians in God our Father and the Lord Jesus Christ: Grace and peace to you from God our Father and the Lord Jesus Christ. We are obligated to thank God for you all the time, brothers/and sisters, as is fitting, because your faith is growing more and more, and your love for one another is increasing. That is why we boast among God’s churches about your perseverance and faith in the face of all the persecution and affliction you are enduring. 2 Thessalonians 1:1-4
In his first letter to the Thessalonians, Paul commended them for their work of faith, labor of love, and enduring hope in our Lord Jesus Christ. (1 Thes 1:3)
In this second letter he thanks God for them because their faith is growing and their love is increasing, their perseverance and faith in the face of all the persecution and affliction they are enduring.
All this is clear evidence of God’s righteous judgment.
All this is clear evidence of God’s righteous judgment. And so you will be counted worthy of the kingdom of God, for which you are suffering. After all, it is only right for God to repay with affliction those who afflict you, and to grant relief to you who are oppressed and to us as well. This will take place when the Lord Jesus is revealed from heaven with His mighty angels 8in blazing fire, inflicting vengeance on those who do not know God and do not obey the gospel of our Lord Jesus. They will suffer the penalty of eternal destruction, separated from the presence of the Lord and the glory of His might, on the day He comes to be glorified in His saints and regarded with wonder by all who have believed, including you who have believed our testimony. 2 Thessalonians 1:5-10
Thank God, we are just now seeing spiritual usefulness increase as Messiah Jesus continues to build his Church in the midst of the persecution we are enduring.
Messiah is blessing us with apostles, prophets, evangelists, pastors and teachers who are leading us to grow up in him and increase in being spiritually useful as each part in his body is working properly.
From Him the whole body, fitted and held together by every supporting ligament, grows and builds itself up in love through the work of each individual part. Ephesians 4:16
Our perseverance and faith in the face of all the persecution endures.
Consider it all joy, my brothers and sisters, when you encounter various trials, knowing that the testing of your faith produces endurance. And let endurance have its perfect ]result, so that you may be perfect and complete, lacking in nothing. James 1:2-4 NASB
The Triumph of Faith
Therefore, since we have been justified through faith, we have peace with God through our Lord Jesus Christ, through whom we have gained access by faith into this grace in which we stand. And we rejoice in the hope of the glory of God.
Not only that, but we also rejoice in our sufferings, because we know that suffering produces perseverance; perseverance, character; and character, hope. And hope does not disappoint us, because God has poured out His love into our hearts through the Holy Spirit, whom He has given us. Romans 5:1-5
Unless noted, all Scripture quoted is from the Berean Study Bible