That shall be your fringe; look at it and recall all of Hashem's [G-D] commandments and observe them, so that you do not follow your heart and eyes in your urge to stray.

The Baal Haturim says that Hashem commanded us to make four Tzitzis at the four corners of the garment so that whichever way one turns he will be reminded of the Mitzvos. Every one of the Tzitzis has 5 knots to remind us of the five books of the Torah. There are 8 strings to remind us not to commit transgressions with any one of the eight limbs that prompt us to do Aveiros, the ears, eyes, mouth, nose, hands, feet, Ervoh and the heart. If one successfully guards himself from transgression, he will merit ascending above 8 heavens and if one commits transgressions he will be judged with 8 punishments, punishment to the body in the grave (Chibut Hakever) and the seven levels of Gehenom.