• Being truthful is evidence of a person's straightforwardness [on the path of Islam] and his soundness. Whenever a person is known to be truthful, people trust his word and benefit from his advice and are secure [in dealing] with him.
• When truth prevails in the society, then people have confidence in passing science, information, and news and [have confidence] in covenants and pacts. [However,] when lying becomes common, then no one trusts anyone else in buying, selling, contracts and dealings, and grudges and quarrels occur between people.
• The prophet (may Allah bless him and grant him peace) has revealed some of the truth's effects. According to al-Hasan bin Ali: that Allah's messenger (may Allah bless him and grant him peace) said: (Abandon what doubts you for that which does not doubt you. Indeed, truth is tranquility and lying is doubt)(1). So, [the truth] is tranquility for the truthful [person]'s soul and comfort for his conscience.
• The prophet (may Allah bless him and grant him peace) has revealed in another hadeeth that the truth is cause for barakah [(i.e. prosperity)] and increase in fortune. According to Hakim ibn Hizam (may Allah be pleased with him), he said: Allah's messenger (may Allah bless him and grant him peace) said: (The two traders have a choice as long as they do not part, and if they are truthful and clear then their sale has barakah [(i.e. prospers)], and if they conceal and lie then their sale's barakah [(i.e. prosperity)] is destroyed(2).
• This is so in this world. As for the hereafter, the prophet (may Allah bless him and grant him peace) said in a hadeeth narrated by ibn Masoud: (Indeed, truthfulness leads to righteousness, and righteousness leads to Heaven, and indeed a man continues to be truthful until he is designated by Allah as a truthful person(3).
According to Sahl ibn Haneef (may Allah be pleased with him): that the prophet (may Allah bless him and grant him peace) said: (He who honestly asks Allah for martyrdom, then Allah grants him the rank of martyrs even if he dies on his bed(4).
1) Produced by al-Tirmithi #2520 and he authenticated it; see Saheeh Sunan al-Tirmithi #2045.
2) Produced by: al-Bukhari #2107 and this pronunciation is his; and Muslim #1531.
3) Produced by: al-Bukhari and Muslim, and was recently referenced.
4) Produced by Muslim #1909.