"The Lamb" and "The Tyger" both originally appeared in Willam Blakes' collection of poetry entitled Songs of Innocence and Experience. William Blake questions the creatures' origins in both "The Lamb" and "The Tyger." In "The Lamb," the speaker questions "Little Lamb, who made thee," and in "The Tyger" the speaker wonders "What immortal hand or eye could frame thy fearful symmetry?" Both of the poems then connect the animals' origins to address a greater theological question about the Creator's role in nature. Through addressing each animals' characteristics and posing further questions, the speaker of "The Tyger" Blake wonders at the fearful construction of "The Tyger" and even references "The Lamb" poem asking:
"Did he who made the Lamb make thee?" (20)
"The Tyger" and "The Lamb" feature animals that are practically opposites; one is a fearsome predator and the other, a gentle, innocent animal. The tones of "The Lamb" and "The Tyger" are strikingly different; Blake uses dark, powerful imagery to create an awed tone in "The Tyger" whereas the tone of "The Lamb" is gentle and crooning.
The organization of "The Tyger" and "The Lamb" is different as well. For "The Tyger" Blake employs quatrains and rhymed couplets which perfectly suggest the rhythmic hammering of the smithy, lending the poem a sense of urgency and power. "The Lamb" uses rhymed couplets as well, but instead of dividing the lines into quatrains, Blake groups them into two large stanzas of five couplets each; this structure complements the message and flow of the poem, giving it a flowing, lyrical quality.
"The Tyger" and "The Lamb" both have many similarities and differences in terms of themes, messages, tone, and organization.
The Tyger and the Lamb are poem from Blakes's collection of poetry called "Songs of Innocence and Experience". That is a good bit of knowledge to keep in mind when determining the themes for the poems.
The next step would be to look at the diction, word choice, for each poem. What sorts of words are used? "burning" "bright" "night" all connote a sense of darkness mixed with heat and passion.
Imagery is also important in determining theme (although the word you are probably looking for is tone). What contrasting images do the poems use?
But I do think that the poems have more or less the same theme. They all (if you take "The Tyger" and "The Lamb" together) are talking about the fact that there is both good and evil in the world. And they are talking about how God must have made both. And they are suggesting that maybe there is a place for both in God's plan.
I guess one thing that may have changed a bit is that I wonder how positively Blake is thinking of the lamb. I wonder if he is thinking that it is too soft just like the clod.