R.A. Torrey emphasizes the significance of open-air meetings in spreading the Gospel, highlighting their scriptural foundation as demonstrated by Jesus and other biblical figures. He outlines the advantages of these meetings, including their portability, ability to attract large crowds, and cost-effectiveness, while also noting their effectiveness in reaching diverse audiences, including backsliders and those who may not attend traditional church services. Torrey encourages believers to conduct these meetings in strategic locations and with proper preparation, emphasizing the need for earnestness and reliance on God. He concludes by stressing the importance of being filled with the Holy Spirit and remaining loyal to God's Word for successful outreach.