"For I want you to know how great a struggle I have for you... (2:1)"
Paul is repeatedly telling the Church in Colossae that he is suffering.
So what was his purpose of letting them know about his struggle? And
what was he struggling for?

The Purpose of Sending Letters in Paul's Days

As Paul wrote in the very end of this letter, he sent this letter from
the prison. So you can tell that one of the cause of his struggle was an
imprisonment. While he was in prison, he received the news about the
love between the church. This led Paul to the thankfulness and prayer
about them. So Paul wanted let them know about his struggle but the
church was also letting him know about what is happening to them by
writing him letters. We can say that one of the main purpose of sending
letters in Paul's days was letting each other know about what is happening.

Struggling for the Church's Sake

In Colossians 1:24, Paul is telling the church that he is suffering for
their sake. And he also said that even the struggle is his joy. Because
suffering for Christ's church also means that they are suffering for
Christ's sake. For the church is the body of Christ and Christ is it's
head. Than what is the struggle for Christ's sake? It is the struggle
for spreading the Gospel but they were also promised that the Glory of
Christ will be shown at the end.

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