Don't forget verse 15:19a - "by the power of signs and wonders, by the power of the Spirit of God".KingdomBuilder wrote:Romans 15:18, emphasis mine“For I will not venture to speak of anything except what Christ has accomplished through me to bring the Gentiles to obedience—by word and deed,”
Roman 1:5 - "Through Him and on behalf of His name, we received grace and apostleship to call all those among the Gentiles to the obedience that comes from faith. emphasis mine
It is the powerful work of the Spirit in the believer that results in obedience.