Acts 16:13
And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither. And on the sabbath we went out of the city by a river side, where prayer was wont to be made; and we sat down, and spake unto the women which resorted thither.
This verse marks the beginning of the proclamation of the gospel in Europe during the journey into Macedonia. It takes place at Philippi, the chief city of that part of Macedonia, and a colony. Paul arrived there with Silas, Timothy, and Luke by a straight course from Troas to Samothracia and the next day to Neapolis and thence to Philippi. They came because after the night vision of the man of Macedonia they were assured that the Lord had called them to preach the gospel there, and the call was so imperative that it admitted no delay.
On the Sabbath the apostles went out of the city to a riverside place where prayer was customarily made, sat down, and spoke the gospel to the women who resorted there. Among the women was Lydia, a seller of purple from Thyatira who worshiped God and whose heart the Lord opened. She received the truth gladly, and she and her household were converted and baptized, after which she entreated the apostles to make her house their home.
After Paul left, Luke remained in Philippi serving as both physician and gospel minister, and his medical skill helped open hearts to the gospel. The verse teaches believers to seek out and join customary places of prayer as often as possible for prayer and communion with God. The verse also teaches trust that God cares for Christians in the place where duty requires them to be. The place where prayer is made is a place for having the Spirit of God, and the Christian spirit that belongs there is just as essential in active business lines.