Jonas first encounters the feeling of love in chapter 16 of The Giver.
What Jonas actually sees in the memory transmitted to him is a group of people of mixed ages sharing in a variety of obviously pleasurable activities - giving and opening presents, cooking together, admiring a decorated tree in the large room. Recalling and describing the scene to The Giver, Jonas is able to identify some of the feelings he observed, including excitement, family, happiness, and warmth. Jonas struggles to identify and understand another sensation, previously unknown to him, that he sensed in the memory.
I couldn’t quite get the word for the whole feeling of it, the feeling that was so strong in the room...“Love,” The Giver told him.