Actually, i am mentioning this because i have encountered this question twice till now (twice too many to tell you the truth!).
There is a Hadeeth (Prophet's saying) that goes: "God Likes sneezing, and dislikes yawning".
إن الله يحب العطاس ويكره التثاؤب فإذا عطس فحمد الله فحق على كل مسلم سمعه أن يشمته وأما التثاؤب فإنما هو من الشيطان فليرده ما استطاع فإذا قال ها ضحك منه الشيطان
I once heard a question about it in person (can't remember where or who), and once read it on a blog.
Her question was: "If i yawn, does that mean God hates me?".
Below was my answer to her...
Don’t mix yourself up.
As for the Tatha2ob 7adeeth (the Prophet's saying i stated above), that is a Sa7ee7 one (proven by years of research by Islamic researchers to be a true Hadeeth said by the prophet).
No need to feel sorry about it.
The reason behind it is explained in another 7adeeth (saying)...
It says the meaning of: "al tatha2ob min al shaytaan" (yawning might be the making of the devil)...
Why is it hated by God?
is because the devil is the one that uses it against us...
how? here's how...
When you pray, have you noticed that you always "tetawby" (yawn) when you read Al Fateha (Quran part read while praying) ?
When you pray, have you noticed that you always "tetawby" when you read Al Tashahod (a part in prayers where we say that there is no God But Allah and that Mohammad is God's Prophet - which is the first pillar in Islam "Saying and Believing inThe Tashahod") ?
That is the devil (waswasa), he uses it to lessen our concentration in prayer...especially, with the tashahod when you are mentioning the Shahada (the main pillar of Islam).
This is not my opinion this is the what the prophet told us.
So, the devil uses it against us in prayers by waswasa...that is why God does not like it.
It has nothing to do with God not liking he\she who does tatha2ob.
It is the issue that the devil is behind it.
As for the 3otaas (sneezing), well it is a scientific fact that the heart stops for a fraction of a second when you sneeze.
So, that is why after sneezing we as Muslims say "al 7amdo lelAh"...thanking HIM for the gift of life (the heart stops yet works again). And since we say AL 7amdo lelAh which is an act God likes, then God likes 3otaas..
Updated Note: When sneezing the heart doesn't stop, it changes beat rate. Yet, thinking of it... the reason for saying thank God is still valid. (Thanks Dr.Zizo for reminding me).
Convinced...not convinced... cool in both cases :p
Mood: Fel lazeez :)