Although the Bible does clearly show that people need to repent for all sins, there is no passage that says that all sins are equal; instead, the Bible shows some sins cause more guilt or damage than others. One passage that clearly shows that some sins are more serious than others is John 19:11, which includes the passage "for this reason he who delivered me up to you has the greater sin." The Bible, however, concludes that sin results in eternal punishment.
How grave a sin is can depend on several things, such as the person's knowledge of whether the act was a sin, how much impact the sin had on other people and how deliberate the person was in committing the sin. The level of rebellion also has an effect on how severe the sin in. The Catholic Church classifies severe sins as grave sins, and some of these include abortion, extortion, blasphemy, murder, perjury and false oaths.
Some Bible passages show that some sins come with worse judgment than others. Matthew 11:22, for example, says, "Nevertheless I say to you, it shall be more tolerable for Tyre and Sidon in the day of judgment than for you." It also shows in 2 Peter 2:20-21 that it is better for people not to be aware of what they're doing is a sin than for them to sin knowingly.