Saint vs Sinner, Citizen vs Foreigner

(KJV) Now therefore ye are no more strangers and foreigners, but fellowcitizens with the saints, and of the household of God;

It is so awesome that the apostles all understood and were not afraid to call the Lord's saved saints.

What power is there in a blood you could not be confident in to cleanse? Why would the saved still be called sinners?

It is the Lord's precious blood that is in question when a pastor still calls His saints sinners.

Maybe they just have not experienced the power of the blood?