It was not for his sake, but with him gone there would be less pressure on this little band of new believers. Through Silas and Timothy, he had kept in close touch with them. Throughout 1st Thessalonians, and especially chapter 3, he repeatedly expresses concern about their faith and spiritual well being. And the list goes on.
Faith opens the door to everything else that follows in Christianity.
Of course that is the eleventh chapter of Hebrews. And when we think about this chapter, verse 6 stands out. Of this verse, two things stand out about faith. The reality of God can be seen in His creation. Just look out into the star-studded and strutted heavens, as the heavenly bodies go reeling through boundless space.