Islamic etiquette from Hisnul Muslim: what to say when someone sneezes, thanks you, praises you, greets you or gives you news.
Upon sneezing
When a disbeliever praises Allah after sneezing
When angry
Upon seeing someone in trial or tribulation
At a sitting or gathering
For the expiation of sins, said at the conclusion of a sitting or gathering
Returning a supplication of forgiveness
To one who does you a favour
To one who pronounces his love for you, for Allah’s sake
To one who has offered you some of his wealth
To the debtor when his debt is settled
To someone who says "May Allah bless you"
What to say upon receiving pleasing or displeasing news
Excellence of sending prayers upon the Prophet (saws)
Excellence of spreading the Islamic greeting
Returning a greeting to a disbeliever
Upon hearing a rooster crow or the braying of a donkey
For one you have insulted
The etiquette of praising a fellow Muslim
At times of amazement and that which delights
Upon receiving pleasant news