When Morgan (Lennie James) is passed out Rick (Andrew Lincoln) says "I'm sorry this happened to you". The same words he said to a walker he killed in the first episode, Days Gone Bye (2010).
In the scene where Rick (Andrew Lincoln) walks around in Morgan's (Lennie James) room, you can see in the background two protection kits for adults, written in Hebrew. The text is: Protection Kit for Adults. Protection kits are distributed by the Israeli Home Front Command.
The names Zach and Eugene can be seen written on the walls of Morgan's room. They are the names of two characters that are introduced in season 4.
In the opening scene the car passes a sign reading, "Erin, we tried for Stone Mountain." A few minutes late the car gets stuck in the mud. When the walkers attack the car, a young girl is wearing a bracelet with the name Erin on it.