Little Lamb who made thee Dost thou know who made thee (lines 1-2)
The speaker – himself a child – calls the lamb "little" as if it were a younger child or a pet. In the first line, he sounds like a curious boy marveling at nature, but in the second, he sounds more like a teacher.
Gave thee such a tender voice (line 7)
Just wait until that lamb hits puberty. Seriously, the lamb is humanized a lot like a pre-pubescent boy.
He became a little child: (line 16)
Youth is one of the links between Jesus, the lamb, and the child. Not all of the Songs of Innocence tie youth and innocence together so closely, but this one does.
I a child & thou a lamb, We are called by his name. (lines 17-18)
In Christian thought, even adults are "children" of God. The poem plays with the literal and symbolic meanings of both "child" and "lamb."