O you who believe!

Why do you say that which you do not do?

This refutes those who neglect to fulfill their promises.

This honorable Ayah supports the view that several scholars of the <b>Salaf</b> held, that it is necessary to fulfill the promise, regardless of whether the promise includes some type of wealth for the person receiving the promise or otherwise.

They also argue from the <b>Sunnah</b>, with the Hadith recorded in the Two Sahihs in which Allah's Messenger said,

ايَةُ الْمُنَافِقِ ثَلَثٌ إِذَا وَعَدَ أَخْلَفَ وَإِذَا حَدَّثَ كَذَبَ وَإِذَا اوْتُمِنَ خَان

There are three signs for a hypocrite:

- when he promises, he breaks his promise;

- when speaks, he lies; and

- when he is entrusted, he betrays. 

And in another Hadith in the Sahih,

أَرْبَعٌ مَنْ كُنَّ فِيهِ كَانَ مُنَافِقًا خَالِصًا وَمَنْ كَانَتْ فِيهِ وَاحِدَةٌ مِنْهُنَّ كَانَتْ فِيهِ خَصْلَةٌ مِنْ نِفَاقٍ حَتْى يَدَعَهَا

There are four characteristics which if one has all of them, he is the pure hypocrite, and if anyone has any of them, he has a characteristic of hypocrisy, until he abandons it. 

So he mentioned breaking the promise among these four characteristics.

We mentioned the meaning of these two Hadiths in the beginning of the explanation of Sahih Al-Bukhari, and to Allah is the praise and the thanks.

Therefore Allah implied this meaning, when He continued His admonishment by saying,

كَبُرَ مَقْتًا عِندَ اللَّهِ أَن تَقُولُوا مَا لَا تَفْعَلُونَ