Fires in the Sky

 is a quest in the Fallout: New Vegas add-on Dead Money.

Quick walkthrough
In this quest the player is told by Father Elijah to send each if the three temporary companions in three different locations. Once you've completed report to Elijah. If you choose to bring God instead of Dog, you will have to convince him to trust you. Once you do, he tells you that requires meat from two Ghost People to keep Dog "in the cage". At this point, two Ghost People will spawn on the map and you will have to go hunt them down. Bring him the meat and he will do his part of the mission.

Detailed walkthrough

 * When you start this mission you will have to make a choice between convincing God to follow you, or to use the voice clip of Elijah to turn him into Dog and taking the easy option to follow you.
 * Once god/dog is your companion head east from the fountain and follow the street signs that direct you to the Salida del Sol South.
 * Fight your way through to the switch station and here you can either lock Dog in to force him to operate the switches or you can convince to God to perform the role.
 * Note: it may be necessary to hunt 2 ghost hunters for there remains so you can stop Dog from emerging. This is only if you chose the option of trying to convince God to do it
 * Easiest way to let God or Dog locked in the cage is activating the holotape you get at start when getting him out of the cage, note that it may be needed some speech conversation option, so save before (needs confirmation).
 * with high intelligence you will be able to rationalize with God. Don't turn him into Dog and he will trust you.  At the switches he will agree to stay behind if you have an intelligence score of 7 or higher.  Read the schematics next to the switches and tell him you'll be able to walk dog through the procedure.  He will agree.