With God, sin is sin. There is no big sin and little sin. It's all judged equally in God's eyes. His ways are not our ways.
God will not allow sin to enter heaven. So without repentance, someone who lies will go to hell just as quickly as someone who murders.
There is only one unforgivable sin, and that is blaspheming against the Holy Spirit. Speaking against the Holy Spirit is equivalent to rejecting Jesus Christ with such finality that no future repentance is possible.
More information about formatting options