It guides to evil actions and to the Fire!
It was narrated that ‘Abd-Allaah ibn Mas’ood said:
“The Messenger of Allah (peace and blessings of Allah be upon him) said: ‘Truthfulness is righteousness, and righteousness leads to Paradise. A person will continue to tell the truth until he is written with Allah as one who tells the truth. Lying is evildoing, and evildoing leads to Hell. A person will keep on telling lies until he is written as a liar.’”
(Narrated by al-Bukhari, 5743; Muslim, 2607)
This hadeeth indicates that whoever continues to speak the truth, it will become a feature of his, and whoever deliberately tells lies and persists in it, it will become a feature of his. This is the same as any other good or evil characteristic, if a person persists in it, it becomes a feature of his.
This hadeeth indicates how serious the matter of telling the truth is, and that it may lead a person to Paradise, and it indicates how ugly lying is and how it may lead a person to Hell. This is in addition to the consequences in this world, for the one who tells the truth will have his words accepted by people, and his testimony will be accepted by judges and he will be liked for what he says, whereas for the liar the opposite will be the case.
(Subul al-Salaam, 2/687)
May Allah guide us to avoid this terrible sin completely! aameen!