This is a heart-warming passage which reminds us that the gospel creates close family bonds.  As people receive Christ, they are born again – becoming children of God (John 1:12).  Therefore, they are spiritual brothers and sisters to each other (1 Thessalonians 1:4).  These are real relationships with genuine desires to see God's blessing come to each other, to support each other in difficulty and a deep longing to be with each other.  For Paul, his sudden departure from the new believers in Thessalonica, because of persecution, was a personal bereavement.
 
Paul's intense longing to see them promoted plans to return.  But each effort was frustrated.  Paul described that as satanic obstruction; and interestingly the Lord did not overrule the Evil One.  It was part of the Lord's plan for them to move on to Corinth.  Even though Paul initially did not want to stay in Corinth, the Lord kept him there for one and a half years (Acts 18:9-11).  It was quite some time before Paul could return to Thessalonica.
 
Although the church there was founded by Paul and his team, it was also living evidence of the powerful grace of God.  People had been transformed through the gospel, and Paul was as excited about them as any parent with a new-born or growing child.  If Paul ever wondered whether his ministry was effective, the church in Thessalonica proved that it was.  And he delighted in the new family bonds: the church and  apostolic team were all one in Christ Jesus (Galatians 3:28).  The congregation in Thessalonica were evidence of the efficacy of the apostolic ministry, which will be honoured when Jesus Christ returns. 
 
It is right to form family bonds in Christ – they are undeniable evidence that we belong to Jesus when we love each other (John 13:35).  That is the mark of a true church.  True affection will lead to a desire to encourage and support each other.  Wherever they may relocate, that affection will long for reunion, correspondence and a deep desire to pray for each other with the conviction that the Lord will hear and answer.  In moments of spiritual weakness, the family bonds remind us that we are united together because we are united to Him.  And whether we are weak or strong, the love of Christian siblings is a unique witness to the world that we are bound to our unique Saviour.