Dost thou know who made thee (line 2)
The poem makes God sound kind of like an auto engineer deciding what bells and whistles to put on the latest model. "Tender voice? Check. Soft fur? Check. Fire-breathing capabilities? Hm. Maybe not." The speaker sounds very confident in God's engineering abilities, but the flip side of judging God by his creation is that you have to ask the same questions about ferocious animals, too. Thus Blake's poem "The Tyger," from the Songs of Experience, asks, "Did he who made the Lamb make thee?" You could think of the speaker of "The Tyger" as the kid from "The Lamb," now grown-up and having to deal with some tough questions about whether the creator was so benevolent after all.
He is called by thy name, For he calls himself a Lamb (lines 13-14)
If you read the Old Testament of the Bible, you'll find a lot of examples of the sacrifice of lambs, rams, and other animals that were valuable to humans. People sacrificed animals in order to gain forgiveness from God. In the New Testament, Jesus marks a revolutionary shift: God offers his son as a symbolic "lamb" on behalf of humanity. Although according to the older tradition humans should have made the sacrifice, God makes it for humans. Is the speaker aware of this significance of the lamb? In John 1:29, Jesus is called "the Lamb of God, who takes away the sins of the world."
He is meek & he is mild, He became a little child: (lines 15-16)
In the Christian tradition, Jesus Christ shares the traits of the lamb, especially gentleness and submissiveness ("meek & mild"). These are also traits we ascribe to little children. Are there other ways to view Christ?