You can like a poem before you understand it, and be moved by it, and in fact, that is a sign that you’re starting to understand it, that you’re reading the poem in a good way. Being moved by a poem — laughing or feeling sad or full of longing — or being excited by it, or feeling (maybe you don’t know why) the “rightness” of the poem is a serious part of reading and liking poetry. You may find what you read to be beautiful, or be reminded of places and times, or find in it another way to look at things. All this can help you to understand the poem because it brings it closer to you, makes it a part of your experience. And the better you understand a good poem, the more you’ll like it. –Kenneth Koch –Reading Poetry — from Sleeping on the Wing (Random House)
I came across this passage out of context on another website, and recognized it as being from the introduction of a collection of poems I’ve taught from before.