The verb translated left behind means “abandoned” or “forsaken” and was used in secular contexts of leaving a loved one behind at death. It expresses how serious Paul’s separation from his friends was. Even though he could have benefited greatly by their assistance and fellowship in Athens, Paul thought it best to send his colleagues to Thessalonica and Macedonia for the well-being of the believers in those places. The kind of sacrifice Paul made indicates again the strength of his pastoral concern