Paul tells us here that God takes the pain and suffering of those who are joined to Christ and He brings good out of it. Many times, for instance, God takes pain and suffering to rivet a person's attention, need, and hope upon Christ and the Good News of the Gospel. I can mention many more things. But I won't because by now you should see the wonder and privilege of being joined by God to Christ. I ask this because every person here including me needs saving.
Every person here is stuck in the mud and mire of sin.
Every person here needs Jesus' cross and Jesus' grave. If you believe in Jesus, you can be and should be. If you have true faith in the Jesus Who died and arose and ascended into heaven and is seated at God's right hand then you can be sure. You can be sure because true faith is a sign that God has joined you to Christ. You can be sure because true faith is a sign that God has forged a golden chain of salvation that joins you, a sinner, to the mighty Savior.