I Thess. 3:2b-3 We sent him to strenghten you, to encourage you in your faith, and to keep you from becoming disturbed by the troubles you were going through. But, of course, you know that such troubles are going to happen to us Christians.
Paul sent his traveling companion and disciple, Timothy, to the church in Thessalonia to help them in their faith and to keep them on track. Timothy was to encourage the church and keep them from becoming overcome by faith's sufferings.
It is important that we encourage one another in the faith. It is so easy to get discouraged. Sometimes people of faith are our worst discouragers. Some people just seem to thrive on discouraging others, especially if they dare to not think the same thimg about things. Circumstances sometimes are discouraging. The things going on in the world can be discouraging. We need to be surrounded by people who will lift us up and spur us on instead of holding us back and dragging us down. If you don't have encouragers in your life, you need to make some changes in whom you associate with and find people who are good for your soul.
Paul reminded the church that things were not always be easy for them because of their faith. Christians ought to expect troublesome times in their lives. It is normal for us because we are surrounded by enemies of the faith. Those who are not of the faith are enemies of God. If we are being true followers of Christ we will face opposition to our faith by those in the world, and sometimes it will cause us much suffering.
When we have encouragers in our life, we will be much better equipped to face our troubles positively without being overcome by them.