Summary
Yeats stands over the cradle of an infant, noting that the angels, sick of the dead, are also there. God is pleased in heaven, as are the "Sailing Seven" to see such a well-behaved infant. Yeats kisses the infant, sad because he knows that he will miss the baby as it grows up.
Analysis
This sweet, simple poem takes a much more traditional, rhyming form than most of Yeats's work. Rather than being a free-form lyrical poem, it is three stanzas of four lines each, rhyming in the pattern ABAB CDCD EFEF. Each line is two iambs.
The "sailing seven" refers to either the planets, or the seven stars of the Pleiades. They link the child to a cosmic order, suggesting that an infants pleasure not only affects human beings, but resonates with the order of the universe as a whole.