2 Corinthians 1:6-7
6 If we are distressed, it is for your comfort and salvation; if we are comforted, it is for your comfort, which produces in you patient endurance of the same sufferings we suffer. 7 And our hope for you is firm, because we know that just as you share in our sufferings, so also you share in our comfort.
“Paul had a radically different view of suffering. Suffering—especially trials and discomfort associated with the advancement of Christ’s kingdom—is God’s way of allowing Christians to become more like Jesus, to suffer for the gospel just as Jesus suffered for it (Philippians 1:29; 3:10). Peter agreed with Paul: Christians should rejoice when they suffer, for in their own suffering they will in some small way experience what it meant for Jesus to suffer for their sins (1 Peter 4:12, 13).” (Life Application Study Bible 1940)
“In addition to drawing people closer to Christ, suffering can also help them grow in their faith. God uses suffering to improve his people and shape them into better Christians. In fact, suffering should be thought of as the necessary pain that accompanies spiritual growth. In Romans, Paul noted that suffering produces perseverance, which, in turn produces Christian character (Romans 5:3, 4; see also James 1:3, 4; 2 Peter 1:6; Revelation 2:2, 19). This passage highlights another benefit to suffering: It teaches the sufferer how to encourage others who are also suffering.” (Life Application Study Bible 1940)
Life Application Study Bible. Zondervan, 2011. p. 1940.