Being truthful means speaking the truth and also saying things that reflect reality.
Being truthful is one of the necessities of a human society, one of the virtues of human behaviour, and brings great benefits, whilst lying is one of the major elements of corruption in human society, and the cause of the destruction of social structure and ties, one of the most evil features of bad conduct, and causes widespread harm. Hence Islam commanded truthfulness and forbade lying.
Allaah says (interpretation of the meaning): “O you who believe! Be afraid of Allaah, and be with those who are true (in word and deeds).” [al-Tawbah 9:119]
Ibn Katheer (may Allaah have mercy on him) said (2/414): “It means: be truthful and adhere to truthfulness, and you will be among its people and will be saved from calamity, and this will make a way out for you from your problems.”
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Allaah says (interpretation of the meaning): “O you who believe! Fear Allaah, and be with those who are true (in words and deeds)” [al-Tawbah 9:119]. In al-Saheehayn and elsewhere it is narrated that ‘Abd-Allaah ibn Mas’ood (may Allaah be pleased with him) said: The Messenger of Allaah (peace and blessings of Allaah be upon him) said: “I urge you to be truthful, for truthfulness leads to righteousness, and righteousness leads to Paradise. A man will continue to be truthful and seek to speak the truth until he is recorded with Allaah as speaker of truth (siddeeq). And beware of lying, for lying leads to immorality and immorality leads to Hell; a man will continue to tell lies until he is recorded with Allaah as a liar.” And it was narrated that ‘Abd-Allaah ibn Mas’ood also said: Lying is not appropriate whether in earnest or in jest. Recite if you wish (interpretation of the meaning): “O you who believe! Fear Allaah, and be with those who are true (in words and deeds)” [al-Tawbah 9:119]. Then he said: Do you find any concession allowing that to anyone?
But there are some instances in which Islam permits lying, if that serves a greater purpose or wards off a greater harm:
These cases include the following:
1- When a person is intermediating in order to bring about reconciliation between two disputing parties.
2- When a man speaks to his wife, or a wife to her husband, concerning matters that will increase the love between them.
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