General Behavior (Kitab Al-Adab)
Dawud :: Book 41 : Hadith 5077
Narrated AbuMalik Al-Ash'ari:
The Prophet (peace_be_upon_him) said: When a man goes into his house, he should say: "O Allah! I ask Thee for good both when entering and when going out; in the name of Allah we have entered, and in the name of Allah we have gone out, and in Allah or Lord do we trust." He should then greet his family.