The sentiments in "Laugh and Be Merry" stand as a tribute to the carpe diem mindset: seize the day while you can. The speaker reminds his audience that life is short and shouldn't be wasted in pessimism or dejection. Instead, he encourages us to enjoy our time on Earth because it is fleeting.
In the first stanza, the speaker acknowledges the trials that mankind sometimes encounters. Yet in these moments, it is important to recall that time on Earth passes quickly; only for a moment do we each exist in this long pageantry of mankind.
The second stanza is a reminder that mankind is God's unique creation. Genesis points out that humans were made in God's image and that He was proud of his handiwork. These lines allude to those verses in the first chapter of Genesis as a reminder that God took joy in mankind—and still exists as a nurturing Father.
The third stanza reminds readers of the importance of a connection to nature. The speaker reminds us to connect with the "deep blue cup of the sky" and the "great stars sweeping by" as we progress through both the happiness and the struggles inherent in living. Nature is presented as a means of faithful encouragement for life's "battles" as well as for times of laughter.
The final stanza emphasizes that none of us are alone on this journey. Together, we will engage in the dance of life until the metaphorical music ends. Therefore, we should enjoy the dance with laughter and merriment, always remembering to appreciate the beauty that exists all around us.
This poem by John Masefield is optimistic in tone and incredibly straightforward and hopeful in its subject. It seems to be a poetic expansion on the idiomatic saying "eat, drink and be merry, for tomorrow we die," which is itself a paraphrase of various verses from the Bible. The idea that our time is brief, and that we should therefore enjoy ourselves with friends while we can, is one to which many poets and philosophers have returned, as Masefield does here.
I'll explain the first stanza here. Hopefully, having the first few lines explained will give some context and help explain the rest of the poem. Also, remember that you can always look up individual words that you find strange or confusing because they often have secondary, archaic meanings.
"Laugh and be merry, remember, better the world with a song": Remember that the "song" of laughter and happiness will make the world a better place. It's implied here that happiness is more helpful to the world than sadness or negativity.
"Better the world with a blow in the teeth of a wrong": The world is a better place when justice is served to those who have done wrong. This line relates to the first and implies that laughter and happiness are ways to seek justice.
"Laugh, for the time is brief, a thread the length of a span": Laugh because our lives are very short, like threads that are merely the length of a span, which can mean either a very short period of time, or the arch or part of a bridge that extends between its supports.
"Laugh and be proud to belong to the old proud pageant of man": Laugh (again—this poem thinks that laughter is really important!), and remember that you belong to all of humanity. This line perhaps encourages the reader to look at the big picture—life isn't just about you, or any one person, but all of humanity and history.
The title of the poem could be a reference to one of a few Biblical passages, one being "A man hath no better thing under the sun than to eat, drink, and be merry" (Ecclesiastes 8:15).
In the first stanza, the message is that it is better to laugh and be positive ("better the world with a song"); better than being negative. If there is some injustice in the world, stand against it (second line). Enjoy life because time is short and honor the proud history of mankind.
The second stanza states that God made the Earth with joy and mirth in mind. Life is to be enjoyed.
In the third stanza, we are told to enjoy the grandeur of the day's and night's skies. We are to engage in the world: "Laugh, battle, work, and drink of the wine outpoured / In the dear green earth, the sign of the joy of the Lord."
The final stanza continues with the theme that we should embrace and enjoy life while we can. Live as if we are all siblings: "like brothers akin." Be happy and positive until the end of your days; get the most out of life: "Glad till the dancing stops, and the lilt of the music ends. / Laugh till the game is played; and be you merry, my friends."