In 1 Thessalonians 2:4 Paul says he spoke to the congregation as someone who was approved by God to be entrusted with the Gospel. This is an important claim and is related to Paul’s apostleship.
First, Paul says he was “approved by God.” This verb (δοκιμάζω) has the sense of being tested for the purpose of determining the genuineness (BDAG). For example, an ore which appears to contain gold can be tested to determine if it is in fact gold as well as the quality of the gold. Only after the test is finished can the ore be described as real gold (as opposed to iron pyrite, fool’s gold). Paul is claiming he has been tested by God and has been given approval for his mission to the Gentles. Ironically, it is his suffering persecution for that is the “proof” he has been tested and approved!
Second, Paul was “entrusted with the Gospel.” He was given a revelation that God’s grace was being extended to the whole world without distinction. Gentiles are now able to be right with God without keeping the Law or converting to a form of Judaism. He says something similar in Galatians 2:7. There Paul describes his commissioning as the “apostle to the Gentiles.” His commission is a trust given him from God and he takes this commission very seriously.
To be “entrusted” with something is perhaps a financial metaphor. When someone invests money they expected the financial manager to wisely invest the money and provide some kind of return on the investment. If the manager loses the money, they have not taken their commission seriously and have failed. The fact is that God tested Paul and approved of him to be entrusted the ministry of the evangelization of the Gentiles, and Paul took that commissioning so seriously that he would not do anything that might possibly hinder that trust from yielding fruit.
There are a number of obvious applications to the modern church that can be drawn at this point. Each church is given by God a commission, a purpose, a ministry. You are called to do something in this community. A church that wants to succeed tries to understand what their purpose is, and evaluate their ministry to get that purpose done.
If you know why you exist and you have a pretty good idea what it is you can do to fulfill that purpose, then you must not doing anything that might detract from that purpose. Paul is saying that his ministry is a success, and it is a success because he is honest and genuine while doing his ministry, that he is not out for money or power, or anything else that might motivate other people.
Are churches (or individuals) “entrusted with the Gospel” in a similar way today? Can (or should) we apply similar tests to churches today in order to decide if they are in fact genuine? I think this might even be applied to individual programs within a church – what do we do as part of church which fulfills our “trust” of the Gospel?