How does the speaker in the rainy day face hardship by the end of the poem

In "The Rainey Day" by Henry Wadsworth Longfellow the speaker shows how all the people face difficulties in life at some time however in the third stanza the mood transmit hope and in this lines for example “Be still, sad heart! and cease repining; Behind the clouds is the sun still shining;” we can notice that the speaker is more optimistic and resolved