Narrated Zayd ibn Arqam:
The Prophet (ﷺ) said: When a man makes a promise to his brother with the intention of fulfilling it and does not do so, and does not come at the appointed time, he is guilty of no sin.
Narrated Abdullah ibn AbulHamsa':
I bought something from the Prophet (ﷺ) before he received his Prophetic commission, and as there was something still due to him I promised him that I would bring it to him at his place…