Symbol Analysis
Line 20: When you read the word "lamb," always first think: symbol of Jesus Christ ("the Lamb of God"). As the tradition holds, animals such as lambs were sacrificed to God or gods in general until God offered his Son, Jesus Christ – his lamb – as the final sacrifice for the sins of mankind. In line 20, Blake references a version of Christianity that states that God created Jesus (Protestant version vs. the Catholic doctrine of the Trinity). In any case, you don’t need to know all the theology, just that it’s a reference to Jesus and an allusion to Christianity. Blake asks whether God, who created Jesus, also created the Tyger. Also, don’t forget that "The Lamb" is the title of another poem by Blake, from the Songs of Innocence; the two poems are often read together. (For more information on "The Lamb," check out "In a Nutshell.")