How do we know that God's call to salvation is effectual?

The biblical view of God's call to salvation is that it is not merely an invitation but a command imbued with power. In the sermon, it is highlighted that God's command to 'open the door' is met with the irresistible grace that draws sinners to Himself. When God commands someone to come, He also equips them with the will and desire to respond. This aligns with biblical truths such as those found in John 6:44, where Jesus states that no one can come to Him unless the Father draws them. It is through God's sovereign grace that individuals are enabled to believe, ensuring that His effectual call cannot be resisted. Thus, it is God's grace working in the hearts of men that guarantees their response to His call.