Welcome to the forums! Here are quick answers.
First of all what is the difference between venial sins and mortal sins.
1 John 5:16 “If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.”
Mortal sin destroys grace. Venial sin damages, but does not destroy God’s grace.
Why must I go to a priest to be forgiven?
Christ specifically gave the Apostles power over sin.
John 20:22-23 "And with that he breathed on them and said, “Receive the Holy Spirit. If you forgive anyone’s sins, their sins are forgiven; if you do not forgive them, they are not forgiven.”
Read also
2 Corinthians 2:10: Paul forgave sins in the person of Christ - as an ambassdor for Christ, he had the authority of Christ in forgiving sins:
2 Corinthians 2:10 King James Version (KJV) “To whom ye forgive any thing, I forgive also: for if I forgave any thing, to whom I forgave it, for your sakes forgave I it in the
person of Christ”
When Paul, or any of the Apostles forgave, it was with the power and authority of Christ Himself.
Also where is purgatory in the Bible?
Christ’s parable of seeking forgiveness before you die:
Matthew 5:25-26: “Make friends quickly with your opponent at law while you are with him on the way, so that your opponent may not hand you over to the judge, and the judge to the officer, and you be thrown into prison. 26 Truly I say to you, you will not come out of there until you have paid up the last cent.” combined with Paul’s words in
1 Corinthians 3:12-15 "Now if any man builds on the foundation with gold, silver, [a]precious stones, wood, hay, straw, 13 each man’s work will become evident; for the day will show it because it is to be revealed with fire, and the fire itself will test **the quality of each man’s work. 14 If any man’s work which he has built on it remains, he will receive a reward. 15 If any man’s work is burned up, he will suffer loss; but he himself will be saved, yet so as through fire.
And if a catholic dies without having the chance to confess any mortal or venial sins out of any will of their own will they still be able to make it into purgatory and then into heaven?
You must die in a state of grace. Mortal sin destroys that state of grace. Venial sins damage grace, but do not destroy it. We must be cleaned up before entering heaven, because…
Revelation 21:27 “Nothing impure will ever enter it, nor will anyone who does what is shameful or deceitful, but only those whose names are written in the Lamb’s book of life.”
What will help you immensely is a copy of
Catholicism for Dummies. It is an excellent resource that clearly explains Catholic beliefs and practices, as well as the reasons behind those beliefs and practices. You will be able to rely on this book for years to come. I learn each time I open my copy.**