Explanations

NAKED= /neɪkɪd/ Bare, with no clothes. The phrase "the naked truth" means: all the truth, without additions.

PASTOR= A protestant priest (protestants are one of the branches of Christianity, together with Catholics, Orthodoxes, Anglicans, etc.). The word "pastor" is Latin for "shepherd", in the sense that he is the leader of a group.

PARISHIONERS= The group of Christians in a parish. A parish is the smallest territorial unit in Christian organization; every parish has one church, and the parishioners are the people attending that church. The pastor, or parish minister, is the priest serving that congregation, and he celebrates mass in that church ("mass" is the name of the Christian religious service, the most important mass is celebrated on Sundays).

REVELATIONS= The last book making up the Christian Bible (the holy book for Christians, largely written by Jews). It is also known by "The Book of Revelation" or sometimes, by its original Greek name, "The Apocalypse" /əpɒkəlɪps/ (which means “the revelation”), since in this book, the apostle /əpɒsəl/ John (one of the 12 main disciples of Jesus) describes the revelations he received from God about the end of times (usually referred mistakenly as "the end of the world") in the form of symbolic visions (though some Christian groups like Jehovah’s Witnesses believe they are literal descriptions of actual future facts).

REVELATION 3:20= The Bible is not one book, but a collection of 66 books, and every book is divided in chapters and every chapter is divided in verses (originally, the Bible was written in verses, as a poem). Quotations from the Bible have this format: Name of the book + Number of chapter + Number of verse. So, for example, if you want to refer to the Gospel of Saint John, chapter 3, verse 8, you simply say John 3:8 (pronounced "John, three to eight").

STUCK IT IN THE DOOR= (stick-stuck-stuck). To stick something may be to fasten or collate it onto a place. It may also mean to push an object into or through another object (but in that case it would be "he stuck it through the door"). Since it is a card, and not a post-it, the most probable meaning here is to insert the card between the door and the door frame.

THE OFFERING= This is the part of the religious service when parishioners give some donation (money) for charity and for the parish expenses. One or more people carry a little basket around the church and people put some money inside. The woman put the pastor’s card in the basket at this point.

CRYPTIC= Codified, written in code.

GENESIS= /dʒenɪsɪs/ (Greek for "origen") The first book of the Bible, where they describe how God created the world and the first man and woman.

CHECK OUT= to investigate, examine, or look at.

CITATION= Quotation, a literal transcription of the original text.

BROKE UP= (break-broke-broken) To break up, in this example, means to start suddenly, as an explosion.

GALES OF LAUGHTER= Sudden, loud happy sounds made by people when they are very amused. Careful with the pronunciation of “Laughter” /lɑ:ftə*/ (from the verb "to laugh" /lɑ:f/ or /læf/ in AmE).

BEHOLD= /bɪhəʊld/ In English speaking countries, the usual version of the Bible for quotations is the Authorized King James Version (or KJV), an English translation of the Bible  completed in 1611, so it uses old fashioned language. One of the words we don’t use in modern English is "Behold", very common in the Bible. It simply means "look!". In modern English, to express that beauty is something subjective, we still say "beauty is in the eye of the beholder" (beholder= the person who beholds, who looks).

GENESIS 3:10 READS= Notice that when we want to say what is written in a place, we often use the verb "read":
- The sign reads: Beware of the dog
- The first line in the book reads "This is the story of my life brought to you, reader".
- On the wall there was a graffiti reading "Religion is not the opium of people. Opium is".

BEHOLD, I STAND AT THE DOOR AND KNOCK= The Book of Revelation describes how, at the end of times, the good will prevail and evil people will perish, being the beginning of a world of piece, love and justice. So when Jesus said "behold, I stand at the door and knock" it means: wake up and change your life, you must be prepared because the end of times may arrive any time and you don’t know when.

I HEARD YOUR VOICE IN THE GARDEN AND I WAS AFRAID FOR I WAS NAKED= In the book of Genesis God created the heavens and the earth, and all the animals in the sea, the air and dry land, and He also created Adam /ædəm/ (the first man) and Eve /i:v/ (the first woman), and they were pure and innocent, and lived together in Paradise (the Garden of Eden /i:dən/ ). They were naked because they had nothing to hide. But God only set one condition: they could eat anything except for the fruit of one tree growing in the centre of the garden (traditionally it is referred to as an apple). The devil, in the shape of a serpent, convinced them to eat that fruit, and because they had disobeyed the laws of God they lost their innocence and they should be expelled from Paradise. When they ate the fruit, God called them to ask what they had done. When Adam and Eve heard the voice of God they hid in the bushes, but God found them there (of course), and when He asked them why they didn’t answer to His call, Adam said "I heard your voice in the garden and I was afraid, for I was naked" (because I was naked). They felt embarrassed at their nudity because now they were not innocent anymore.
This story was written to explain that going against the laws of God is the origin of suffering.