What general idea is developed in "Ode to a Nightingale"?

John Keats's "Ode to a Nightingale" presents the general idea of the conflicted nature of life:  pain/joy, pleasure/numbness, life/death, mortal/immortal, real/ideal.

The nightingale acts almost as a muse for the poet's reflections as he moves from his initial response to the song of the nightingale to the poet's distancing of himself from the bird in the final stanza.

For instance, in Stanza I the poet, whose

heart aches and a drowsy numbness pains/My sense, as though of hemlock

is touched by the bird's song, causing him to wish that he could reach a state of numb astraction with the bird and

,,,leave the world unseen, And with thee fade away into the forest dim

by becoming numb through drinking "a beaker full of the warm South."

As a transition into the next stanza, Keats repeats the word fade; however, fade moves into dissolve as Keats contemplates death, not just a numbness to pain as he moves to Stanza IV in which he tells the "darkling" that he has been

half in love with easeful Death," and "Now more than ever it seems rich to die,/To cease upon the midnight with no pain,/while thou art pouring forth thy sould aborad/In such an ectasy!

Here Keats separates himself from the nightingale as he realizes that the "immortal Bird" is not meant for death:  There is a continuum for it as the "self-same song" has been heard by Ruth and others of the ages.  He bids "Adieu!" to the bird as is "tolled" by the song back to his "sole self" and reminded of his mortality. With all these conflicting musings,  Keats wonders in the last line of the ode if his thoughts are merely illusionary, "a waking dream."

Can you explain "Ode to a Nightingale" stanza by stanza?

This ode by John Keats is based upon the single conceit that the little nightingale that the poet addresses is immortal:

1. It assumes that the bird is the only one that has ever existed because it looks and acts the same as birds of this species have for centuries.
2. It assumes that the nightingale is immortal since, unlike humans who fear death, it cannot conceive of death.
3. It assumes that the bird is immortal because the nightingale stands for the ravished princess Philomela's metamorphized soul.

• Stanza I

As a Romantic poet, Keats validated emotional expression as an aesthetic source of experience. In this stanza, then, he expresses his unhappiness, saying it is not envy of the bird's lighthearted song of "summer in full-throated ease." 

• Stanza II

In his melancholy, the poet wishes that he could drink "a beaker full from the fountain of the Muses on Mt. Helicon," where waters of inspiration flowed. With the nightingale, he could disappear into the forest away from his trials in life. Here, the poet revels in the idea of the glorified past, both classical and medieval.

• Stanza III

In the continuation of his wish to "fade away," the poet wishes to leave the cares and anxieties of his life:

Where but to think is to be full of sorrow
and leaden-eyed despairs

for the beauty and wonder to the next, where Beauty and new Love know nothing of this sorrow.

• Stanza IV

The poet tells the nightingale to fly away because he will come on the "wings of Poesy"; that is, with his imagination, the poet will connect both to this world and that of poetic fancy. In line 35, the poet is suddenly transported,

Already with thee! tender is the night....
But here there is no light

but the nightingale lives in darkness. Because the imagery here is connotative of night, the poet may be sleeping.

• Stanza V

Hovering between the real world and the world of the spirit, the poet touches what he cannot see and describes all with colorful imagery:

Fast fading violets covered up in leaves:
And mid-May's eldest child,
The coming musk-rose, full of dewy white,
The murmurous haunt of flies on summer eves.

• Stanza VI

In this stanza, Keats expresses his obsession with death and envisions his soul with that of the nightingale, but if he dies they will part.

To cease upon the midnight with no pain,
While thou art ouring forth thy soul abroad
In such an ecstasy!

• Stanza VII

The poet realizes that the nightingale is not meant for death; his voice is immortal as the voice of the bird has been the same for ages and is ubiquitous: 

This voice I hear this passing night was heard
In ancient days by emperor and clown...

• Stanza VIII

This musing of the poet is but transitory, and he must return to the real world,

Forlorn! the very word is like a bell
To toll me back from thee to my sole self!

While the little nightingale's song has elevated his spirit, the poet wonders if he is awake or dreaming,

...the fancy cannot cheat so well 
As she is famed to do....

The poet has had a transcendent experience, connecting with Nature in the creation of his art, but he is left disappointed as he feels a certain disillusionment in the limits of the imagination. "Ode to a Nightingale" is a beautifully personal lyric by the Romantic poet, John Keats, who loved the classical world, and all that is an expression of the aesthetic.

What does the poet convey in the final stanza of "Ode to a Nightingale"?

Forlorn! the very word is like a bell To toll me back from thee to my sole self! Adieu! the fancy cannot cheat so well As she is famed to do, deceiving elf. Adieu! adieu! thy plaintive anthem fades 75 Past the near meadows, over the still stream, Up the hill-side; and now 'tis buried deep In the next valley-glades: Was it a vision, or a waking dream? Fled is that music:—do I wake or sleep?

The last word of the preceding stanza is "forlorn." It concludes two of the most famous lines in English poetry:

Charm'd magic casements, opening on the foam
Of perilous seas, in faery lands forlorn.

(Evidently the faery lands are forlorn because nobody believes in them anymore--except a few poets like Keats.)

The poet has been trying to escape from the painful world of reality by using his imagination, and he has succeeded in doing so for some time. But the poem has to end. The speaker has to come back to reality. He repeats the word "forlorn," which does indeed sound like a deep, somber bell with the repetition of the "or" sound, and begins to describe his return to reality. He says that his imagination can't provide as much escape and relief as is popularly believed. At the same time that he is leaving the nightingale, the nightingale is leaving him. It is flying away

Past the near meadows, over the still stream,
Up the hill-side; and now 'tis buried deep
In the next valley-glades:

At the end he is back where he started from in the very first stanza. He has managed to escape from reality for a little while (without the aid of that delicious beaker of wine with the beaded bubbles winking at the brim which he imagined); but now he is back in cold reality, and the word that describes his feeling is "Forlorn." He has taken the reader with him on a magical journey all the way back to biblical times and even beyond. What is left is a marvelous poem captured on paper for posterity--one of the most famous poems in the English language.

How would you paraphrase stanza 4 of "Ode to a Nightingale"?

The fourth stanza of this excellent poem sees a distinct change of tone compared to the somewhat somber content of the previous stanzas. It begins by the speaker declaring that he will "fly" to join the nightingale, and therefore escape the pain and suffering mentioned in stanza 3 on the wings of poetry. The rest of the stanza features a beautiful comparison between the night sky and the earthly realm. The moon is depicted as an enthroned queen surrounded by her fairy star attendants, but the earthly realm where Keats and we live is characterised by its darkness and gloom:

But here there is no light,
Save what from heaven is with the breezes blown
Through verdurous glooms and winding mossy ways.

Thus this stanza is an important part of the poem as it presents another comparison between the realm of the nightingale and the realm of humans.

What are some quotations from "Ode to a Nightingale"?

Are you seeking "tender is the night," a phrase used by F. Scott Fitzgerald as the title of his 1934 work about an American psychologist Dick Diver and his wife Nicole, who is psychologically disturbed?  Set in southern France with a  cast of characters much like the real friends of the Fitzgerald's--wealthy, idle, sophisticated and dysfunctional-- the novel has autobiographical overtones as Zelda Fitzgerald herself was mentally unstable.

I think you will derive a better answer with a bit more clarification.  The poem itself is loaded with powerful lines.  I have included a couple and encourage you to revisit these lines in the context of the poem to gain a greater and much deeper appreciation for Keats' words and employment of language:

Fade far away, dissolve, and quite forget What thou among the leaves hast never known, The weariness, the fever, and the fret Here, where men sit and hear each other groan;

Where palsy shakes a few, sad, last grey hairs, 25 Where youth grows pale, and spectre-thin, and dies; Where but to think is to be full of sorrow And leaden-eyed despairs;

Away! away! for I will fly to thee, Not charioted by Bacchus and his pards, But on the viewless wings of Poesy,

Already with thee! tender is the night, 35 And haply the Queen-Moon is on her throne,

Was it a vision, or a waking dream?

Fled is that music:—do I wake or sleep?

The "tender is the night" quote is a fairly powerful one.

Can you critically analyze "Ode to a Nightingale" by John Keats?

A critical analysis of a work of literature is the presentation of one's opinion about a particular work, and this opinion must be backed up by close critical reading and a sound understanding of the text one is evaluating. An example of a critical analysis of John Keats' "Ode to a Nightingale" might proceed as follows:

In the poem, Keats grapples with many important ideas, and one of the most important ideas he touches on is the desire to escape the human condition. Depending on how you look at it, the nightingale can symbolize art, nature, and more. In any case, the nightingale represents a state of being set apart from the human condition, and it is this state that Keats primarily envies. Indeed, the poet wants to transcend his own experience and live in the happier state of being that the nightingale represents. By doing so, he also hopes to escape the human condition, which he characterizes as an experience fraught with toil, hardship, and misery. In other words, Keats imagines the nightingale to represent an idealized world free from the anguish of human mortality and suffering, and it is this idea that informs most of his poetic musings. With this context in mind, it makes sense that the first words of the poem are "My heart aches" (1).