What lesson is the mother trying to teach her son, based upon what she tells him toward the end of the poem?
So boy, don’t you turn back.Don’t you set down on the steps’Cause you finds it’s kinder hard.Don’t you fall now—
There are three pieces of advice here: not to turn back, not to sit down, and not to fall. In life, therefore, she is telling her son to persevere no matter what happens. He must not be discouraged and give up. He must not rest from his labors. He must be careful.
The mother uses the example of her own life to teach her son that life is hard and perhaps rather squalid, since the images of tacks, splinters, and boards torn up suggest stairs in a parlous state. The image of a crystal stair conveys a path which might be hard but is smooth, clear, and polished. Her own stairway has been none of these things—it has been fraught with pains and obstacles. He should expect just the same or, at any rate, his own version of the challenges she has faced.
The final three lines suggest that the son should be able to draw inspiration from the adversity his mother has conquered. Life is hard, she tells him, but the difficulties are not insuperable, and I am living proof of this—hence you too should keep going.
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