When adults think of God’s love for us, we immediately think about Jesus dying on the cross for our sins. For young children though, those concepts are very abstract. It’s important they hear them even though they can’t quite understand it fully. When you want young children to understand God’s love for them however, you want to also use some very concrete things. Things they can see, touch, smell.
One of the best ways to explain to a young child about God’s love is to help them experience the great variety in God’s creation. Tell them the story of creation found in the first part of Genesis. Explain God could have created anything he wanted to create. He could have decided one kind of fish or tree or flower was enough for us.