The Bible does not have a list labeled "the seven deadly sins." This list in question, however, was likely the creation of a Catholic Church monk around the 4th century A.D. It was retained by the church's theologians starting in the Middle Ages (1913 Catholic Encyclopedia article on Sin). Catholics officially teach that there are a minimum of seven deadly (capital) sins that humans can indulge in.
Interestingly, the Catholic list is not a collection of the worst offenses man can commit. It is a list, however, of what they consider are the foundational attitudes that are a starting point for all other disobedience to the Eternal. The most common list of seven attitudes they consider deadly are wrath, greed, lust, pride, envy, sloth and gluttony.
Old Testament Disobedience
The nearest thing in the Old Testament to a list of acts or attitudes considered deadly is in the sixth chapter of the book of Proverbs. Solomon writes that God especially hates seven things.
These six things the Lord hates; yea, seven are an abomination unto Him:
A proud look, a lying tongue, and hands that shed innocent blood, a heart that plots wicked imaginations, feet that are swift in running to evil, a false witness who speaks lies, and he who sows discord among brethren. (Proverbs 6:16 - 19, HBFV throughout).
The only thing clearly in common, however, between the list of what God hates recorded in Proverbs and what Catholic's believe are the seven deadly sins is the attitude of pride.
Not Exactly Seven
The New Testament has at least two lists that delineate several, but not exactly seven, major sins.
The first list is found in 1Corinthians 6:9 - 10 where the apostle Paul states adulterers, thieves, drunkards, extortioners, the covetous and so on will not receive eternal life.
Don't you know that the unrighteous shall not inherit the kingdom of God? Do not be deceived; neither fornicators, nor idolaters, nor adulterers, nor abusers of themselves as women, nor homosexuals,
Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God. (1Corinthians 6:9 - 10).
The second list, found in Galatians 5:19 - 21, states that those who practice fornication, idolatry, sorcery, spreading dissensions and heresies, contentious behavior and still others will not be in God's kingdom!
Now the works of the flesh are manifest, which are these: adultery, fornication, uncleanness, licentiousness, idolatry, witchcraft, hatred, strifes, jealousies, indignations, contentions, divisions, sects,
envyings, murders, drunkenness, revelings, and such things as these; concerning which I am telling you beforehand, even as I have also said in the past, that those who do such things shall not inherit the kingdom of God. (Galatians 5:19 - 21).
Definition of Disobediance
Ultimately, the Bible teaches that sin, defined as the transgression of any of the laws of God, if not repented of will bring the penalty of eternal death. The Bible refers to knowingly, and willfully, rebelling against God's way as the unpardonable sin. The apostle John reveals the standard by which we can know whether we are sinning before God or not.
And by this standard we know that we know Him: if we keep His commandments. The one who says, "I know Him," and does not keep His commandments, is a liar, and the truth is not in him (1John 2:3 - 4).
The book of Galatians records (as well as many other books) that all mankind, from the greatest to the least, sins in far more ways than just seven! The book of Romans further specifies that those who do so must pay with their lives!
For the wages of sin is death, but the gift of God is eternal life through Christ Jesus our Lord. (Galatians 3:22, see also Romans 6:23).
Thankfully, God has provided a way for us to be forgiven of all disobedience (and not just seven deadly sins), through the unselfish sacrifice of Christ (Romans 5:8). He forgives us not only 7 times (the number Peter thought was the upper limit, see Matthew 18:21) but is gracious and merciful to overlook our trespasses as many times as it takes (verses 21 - 22)!