Swearing

Narrated Abu Hurayrah Radhiyallahu anh:
The Prophet Sallallahu alihiwassalam said: Do not swear by your fathers, or by your mothers, or by rivals to Allah; and swear by Allah only, and swear by Allah only when you are speaking the truth.

(Sunan Abi Dawood)

I remember when I was in school, and I did not know about this then, and I used to say, "Mother promise" etc, hearing my peers say the same. Only Allah has the right to swear by His creations, like وَالضُّحَى, وَالتِّينِ وَالزَّيْتُونِ , وَالْعَصْرِ etc. We should swear only by Allah Azza Wajal.