بِسْمِ اللَّهِ وَلَجْنَا، وَبِسْمِ اللَّهِ خَرَجْنَا، وَعَلَى اللَّهِ رَبِّنَا تَوَكَّلْنَا

In the Name of Allah we enter, in the Name of Allah we leave, and upon our Lord we depend

Bismillaahi walajnaa, wa bismillaahi kharajnaa, wa 'alaaRabblnaa tawakkalnaa

Then say As-Salaamu 'Alaykum to those present.

Abu Dawud 4/325. Muslim 2018 states that one should mention the Name of Allah when entering the home and when beginning to eat; and that the devil, hearing this, says: 'There is no shelter for us here tonight and no food.