What is meant by being 'chosen in the Lord'?

Paul mentions individuals like Rufus as being 'chosen in the Lord' to signify not only their election by God before the foundation of the world but also their particular roles within His ministry. This highlights the sovereignty of God in salvation and the unique tasks given to different believers. Each member of the church has a specific role, reflecting God's purposeful design for His kingdom. The notion of being chosen incites humility and gratitude, affirming that salvation and service arise solely from God's grace and not from personal merit.