Answer:
For the first question the answer is Martin Luther have never read the Bible since on his timeline the Bible was too expensive and only a few can be produced and for the second question the reason why Martin Luther was so confident was because he believed that even though we sinned and deserves death and hell as long as we have faith in Jesus Christ he will give us salvation.
Explanation:
2) Before the invention of the printing press, Bibles and other books were written and illustrated by hand. It would take several years to produce a single book in this way, which made them very expensive.
4) Those who see God as angry, do not see him rightly. If we truly believe that Christ is our Savior, than we have a God of Love, and to see God in faith is to look upon His friendly heart. So when the devil throws your sins in your face and declares that you deserve death and hell, tell him this: “I admit that I deserve death and hell, what of it? For I know One who suffered and made satisfaction on my behalf. His name is Jesus Christ, Son of God, and where He is there I shall be also!
~Martin Luther~
Martin Luther believed that salvation is a gift from God that is granted to sinners who have their faith in Chris and something a sinner can obtain through the performance of good works.
I hope this helps :)
