Sidq is more than not lying. It is when your words, your face and your life all say the same thing. The Prophet ﷺ described it as a road: a person keeps walking it until Allah writes him down as truthful Bukhari 6094.
From the Quran
يَا أَيُّهَا الَّذِينَ آمَنُوا اتَّقُوا اللَّهَ وَكُونُوا مَعَ الصَّادِقِينَ
From the Prophet ﷺ
«إِنَّ الصِّدْقَ يَهْدِي إِلَى الْبِرِّ، وَإِنَّ الْبِرَّ يَهْدِي إِلَى الْجَنَّةِ، وَإِنَّ الرَّجُلَ لَيَصْدُقُ حَتَّى يَكُونَ صِدِّيقًا»
Seen in the prophets
Allah describes Ibrahim with the strongest form of the word: "He was a man of truth, a prophet" 19:41. Siddiq: truth all the way through.
A man who had shared a prison cell with Yusuf came back years later and called him by the thing he remembered most: "Yusuf, O truthful one" 12:46. Prison had not changed what people knew about him.
On the hill of as-Safa he asked Quraysh if they would believe him if he warned them of riders in the valley. They answered: "Yes, we have never known you to say anything but the truth" Bukhari 4770. Even the people who rejected his message trusted his word.
What it is not
Sidq is not saying every hurtful thing that happens to be true. The same Prophet ﷺ said: speak good, or stay silent Bukhari 6018. Truth with a good word, or a kind silence. Never a lie.
Today, in practice
Don't send "on my way" before you have left.
When you were wrong, say "I was wrong", with no "but" after it.
Let the person you are online and the person you are at home be the same person.
Small, practical steps. This is friendly advice, not a ruling.
Your manner for the week
الصِّدْق Truthfulness
Choose one manner and carry it for seven days. It is saved on this device only, nobody else sees it.
Their moments
Sources on this page
Quran 9:119Quran 12:46Quran 19:41Sahih al-Bukhari 4770Sahih al-Bukhari 6094
Quran meanings are given in plain English, close to the Arabic. Hadith numbers follow sunnah.com.