Anyone who says they believe the Bible but they don't sincerely try to put its commands into practice is a hypocrite.
The Bible contains clear instructions on how to be forgiven for one's sins by God (through putting total faith in what Jesus did to legally pay for sin). It tells the forgiven sinner to stop sinning - to turn around and walk in the opposite direction from sin and to start following Jesus. It commands believers to seek fellowship with other believers and to worship God in the community of the gathered church. It commands the new Christian to start sharing the good news about Jesus, to pick up their cross daily in order to follow Christ.
If the Bible isn't lived out 24/7, a person is all talk and no walk.