(This email conversation with a Free Presbyterian friend earlier in the week seems apt today).
Protestants believe what the Bible says, that 'all have sinned'. No-one is made right with God by their own achievements. 'Filthy rags' is what the Bible calls even our best efforts. There are no infallible saints, just sinners.
The Bible itself has just one 'Hero' - Jesus Christ. Every book in the Bible, in some way, points to Jesus. Every other person in scripture, and in all of human history, is a failure.
Despite human failings, God in His mercy and grace saw fit to use imperfect men and women throughout the Bible, and throughout history, to tell others of His perfect good news - that our salvation is 'by faith alone in Christ alone'. Jesus Christ alone is perfect, and His righteousness covers our sin completely when we put our trust in Him.
Christ is completely sufficient. There is no additional 'penance'. There is no additional church tradition to be observed. As He said Himself, 'It is finished".
May God be with the Paisley family in their time of bereavement. "For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know..." - I Corinthians 13:12