Helpful scripture for understanding difficult faith questions

Helpful Scripture for understanding difficult faith questions
 
Why do we celebrate the Eucharist and believe it to be the real body of Christ?
The cup of blessing that we bless, is it not a participation in the blood of Christ? The bread that we break, is it not a participation in the body of Christ?
– 1 Corinthians 10:16

Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. Whoever eats my flesh and drinks my blood has eternal life, and I will raise him on the last day. For my flesh is true food, and my blood is true drink.
– John 6:53-55
 
Why do we have such a lengthy preparation to receive Communion and why can’t other Christians take Communion – isn’t Jesus for everyone?
Therefore whoever eats the bread or drinks the cup of the Lord unworthily will have to answer for the body and blood of the Lord. For anyone who eats and drinks without discerning the body, eats and drinks judgment on himself.
– 1 Corinthians 11:27,29

How do we know that the Catholic Church was started by Jesus and that it will never be overcome by evil?
And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.
- Matthew 16:18

Why do Catholics go to Confession, what right does the priest have to forgive our sins?
When he had said this, he breathed on them (the apostles); and he said to them: Receive ye the Holy Ghost.
Whose sins you shall forgive, they are forgiven them: and whose sins you shall retain, they are retained.

– John 20: 22 -23

Why do Catholic Priests and Nuns chose to not get married?
I would like you to be free from concern. An unmarried man is concerned about the Lord’s affairs – how he can please the Lord. But a married man is concerned about the affairs of this world – how he can please his wife –  and his interests are divided. An unmarried woman or virgin is concerned about the Lord’s affairs: her aim is to be devoted to the Lord in both body and spirit. But a married woman is concerned about the affairs of this world – how she can please her husband.  I am saying this for your own good, not to restrict you, but that you may live in a right way in undivided devotion to the Lord.
- 1 Corinthians 7:32-35
 
For there are different reasons why men cannot marry: some, because they were born that way; others, because men made them that way; and others do not marry for the sake of the Kingdom of heaven. Let him who can accept this teaching do so
– Matthew 19:12
 
Why do Catholics have Baptism and then Confirmation, whereas in some other churches you can just be “saved”?
For the Holy Spirit had not yet come down on any of them; they had only been baptized in the name of the Lord Jesus. Then Peter and John placed their hands on them and they received the Holy Spirit.
– Acts 8:16-17
 
Why do Catholics have a Magesterium explaining the Scripture, why can’t we just take the Bible and start teaching our own interpretation as truth?
Above all else, however, remember that no one can explain by himself a prophecy in the Scriptures.
– 2 Peter 20