ANSWER: The Bible does not have a list called 'the seven deadly sins.' A Catholic Church monk around the 4th century A.D. likely started this list. It is not so much a collection of the worst offenses man can commit, as it is a list of what Roman Catholics consider are the worst attitudes that are the basis for all disobedience to the Eternal. The most common list of attitudes considered "deadly" are wrath, greed, lust, pride, envy, sloth and gluttony.
The nearest thing in the Old Testament to a list of seven sins considered deadly is in the sixth chapter of the book of Proverbs. Solomon writes that God hates those who is full of pride, a liar, a murderer of those who are innocent, a person who devises ways to do evil and those who are eager to do wrong. He also hates those who bear false testimony against another person and those who seek to pull people apart through sowing seeds of contention (Proverbs 6:16 - 19). The only thing clearly in common, however, between the list of what God hates and what Catholic's believe are the seven worst sins is the attitude of pride.
The New Testament has at least two lists that delineate sins or bad behavior. These lists, once again, are very different from the one in your question. The first list is found in 1Corinthians 6:9 - 10. The apostle Paul states that the following people will NOT receive eternal life - adulterers, thieves, drunkards, extortioners, the covetous and so on. The second list, found in Galatians 5:19 - 21, again states that those who practice the following will NOT be in God's kingdom - fornication, idolatry, sorcery, outbursts of wrath, those who spread dissensions and heresies, those who have selfish ambitions, those who are contentious, and still others.
Ultimately, the Bible teaches that sins, which it defines as the transgression of ANY of the laws of God, if unrepented of brings the death penalty. We might grade them but God does not, as ANY one of them is deadly!
3. And by this standard we know that we know Him: if we keep His commandments. 4. The one who says, "I know Him," and does not keep His commandments, is a liar, and the truth is not in him.
4. Everyone who practices sin is also practicing lawlessness, for sin is lawlessness (1John 2:3 - 4, 3:4)
22. But the Scriptures have shut up all things under sin, so that by the faith of Jesus Christ the promise might be given to those who believe (Galatians 3:22)
23. For the wages of sin is death, but the gift of God is eternal life through Christ Jesus our Lord (Romans 6:23)
Thankfully, God has provided a way to be forgiven, through the unselfish sacrifice of Christ (Romans 5:8). The Eternal does not stop at only forgiving us or being gracious to us seventy times seven times (Matthew 18:21 - 22). He promises there will come a time when He will decide NOT to remember our sins FOREVER!
No more shall every man teach his neighbor, and every man his brother, saying, 'Know the Lord,' for they ALL shall know Me, from the least of them to the greatest of them, says the Lord. For I will forgive their iniquity, AND THEIR SIN I WILL REMEMBER NO MORE (Jeremiah 31:34)
Thank you for your question regarding whether of not a list of seven deadly sins exists in God's word.