The Prophet ﷺ counted a good word as sadaqah, a charity, just like giving money Bukhari 2989. It costs nothing at all, and most of us are still stingy with it.
From the Quran
وَقُولُوا لِلنَّاسِ حُسْنًا
From the Prophet ﷺ
«وَالْكَلِمَةُ الطَّيِّبَةُ صَدَقَةٌ»
Seen in the prophets
Musa and Harun were sent to Pharaoh, a ruler who killed children, and Allah told them: "Speak to him with gentle words, so that perhaps he will remember, or fear" 20:44. If Pharaoh was owed gentle words, so is your brother.
Ibrahim's father worshipped idols and threatened to stone him. Ibrahim began every sentence with "O my father", and answered the threat with "Peace be upon you" 19:42-47.
'Abdullah ibn 'Amr said the Prophet ﷺ was never foul in his speech, and never tried to be. He used to say: "The best of you are the best in character" Bukhari 6035.
What it is not
A good word is not flattery, and it is not lying to be nice. It is the truth, said the way you would want it said to you.
Today, in practice
Thank the person behind the counter, and look at them when you do.
Before you post a comment, read it back as if it were written about your sister.
In an argument, name one thing the other person got right.
Small, practical steps. This is friendly advice, not a ruling.
Your manner for the week
الكَلِمَةُ الطَّيِّبَة The good word
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 2:83Quran 19:42-47Quran 20:44Sahih al-Bukhari 2989Sahih al-Bukhari 6035
Quran meanings are given in plain English, close to the Arabic. Hadith numbers follow sunnah.com.