The most essential feature of Iqbal’s poetry lies in his mastery in expanding the language made available to him by the variety of poetries in Persian and Urdu and also in his ability to maintain an interactive contact with the variety of poetries produced in other languages, especially English and German. His creative communion with the poetries of the past and present and conscious effort not to write in isolation made him, on the one hand, adhere to the classical rigours of Persian and Urdu poetry and achieve capacious waywardness of western poetry, on the other; all his poems partake of both these qualities. His idiom and style overwhelmed post_Iqbal Urdu poetry and have been imitated and recycled to the extent that it is very difficult to appreciate his formal innovative skill in welding the two qualities. He, in tune with the Platonic notion of inspiration from “ghaib” (the invisible divine force), believed that a poet’s ability to “contrive” new meanings is ingrained in his nature, but, at the same time, is made communicative to others through poet’s conscious training in the craft. Though his theory of poetry is not available to us in any of his prose works, it is amply expressed both through his own poetic practice and in many a stray statement about the mystique of creativity obtaining in his poems.

Here is a summary statement on his notion of poetry taken from zarb-I kaleem :

Har chand ki ijaadi m’aani hai khudaadaad
koshis se kahaan mard-I hunermand hai aazaad
khooni ragi m’emaar ki garmi se hai t’amir
maikhana-I Hafiz ho ki butkhaanai Behzaad
be mihnate paiham koi  jawher nahin khulta
Roshan sharari tesha se hai khaanai Farhaad

Invention of meaning is a divine gift, notwithstanding,
never can a man of skill be free from unfailing effort;
Nothing but the heat of blood in arteries is expressed,  
Be it Hafiz’s tavern or the idol-house of Behzad.
No gem gets unravelled without unceasing strife,
Farhad’s abode is illumined by the sparks of his hammer.

(Tr. S.S.)

While regarding inspiration as the echo of a sublime soul, he never ignored the poet’s vocation as a rational artist in giving shape and structure to utterances under the direction of a social responsibility and commitment to be effective in achieving the desired array in the order of things. Iqbal, like the author of Peri Hupsous, namely, Longinus, believed that poetic ecstasy occurs in a sublime soul in very brief spurts of energy. Poet’s task is to retrieve the primeval beauty of seemingly ordinary objects from the dust of the routine and then re-energise them with the “ soz-i darun” that is a latent faculty of a creative mind. With his emphasis on strife and conscious effort to untangle the skeins of experience, Iqbal does not regard poetry as a spontaneous overflow of the ecstasy, but as poet’s rational effort to find the most approximate equivalent to amorphous experience or the halo of light that he discovers in things around; it is a strenuous strife with the already existing language, no less  painful than Farhad’s endeavour to make rivulet of milk run through rocks.  

Rang ho ya khisht wa sang, chang ho ya harf wa saut
M’jizai fann main hai khuni jigar se namud
Qatrai khuni jigar silk o banata hai dil
   Khuni jigar se sada wa sarur wa sarud.

The “unsolicited” inspiration comes in the form of transient flashes, but not to a mind, however potent in terms of natural propensity it may be, that remains passively in wait for the ecstatic moments; the poet’s mind has to remain restively in search of the celestial brilliance that is  always abundantly present in every bit of nature.

darin gulshan parishan misli boyam
nami danam chi mi khwaham chi joyam
barayad arizu ya bar nayayad
shahid-I soz wa saz-i arizooyam

A restive gale of fragrance I am in this garden,
not knowing what I desire and what I seek;
unmindful of the wish’s fulfilment or deprivation,
a martyr of the music of desire I am.

(Tr. S.S.)

The finds of the creative quest find corresponding echoes in the gifted mind. This notion of Iqbal’s creative process is, in many respects quite identical with Coleridge’s account of higher meaning of nature the discovery of which is the activity of spirit that results in “self-realizing intuition”. Coleridge wrote:
In looking at objects of Nature while I am thinking, as at yonder moon dim-glimmering through the dewy window-pane, I seem rather to be seeking, as it were asking for, a symbolical language for something within me that already and forever exists, than observing anything new. Even when that latter is the case, yet still I have always an obscure feeling as if that new phenomenon were the dim awaking of a forgotten or hidden truth of my inner nature.
( Coleridge, 1895. Anima Poetae, p. 115.)
Iqbal expresses his concept of natura naturans, the interactive communion between nature in the sublime sense and creative soul, in many a beautiful verse. Here is a short poem from payam-i mashriq, titled huur wa shaair ( The Houri and the Poet) that he wrote in reply to Goethe’s poem of the same title:

Houri:
Na ba baadah mail daari nab a man nazar kushaai
Ajab in  ki  tuu nadaani rah-wa rasm-I aashnai
Hamah saaz-i  justajue  hama soozi aarizuue
Nafase ki mai guzaari ghazale ki mai sarai
Ki arm ba chshm aayad chu tilsm simyaie

Poet:
Dil-e rahravaan farebie ba klaam-e neish daarie
Magar ien ki lazzate o narasad ban auk-e khaare
Chi kunm ki fitrate man ba maqaame dar nasaazad
Dile naa sabuur daaram chu sabaa ba laala zaare
Chu nazar qaraar gierad ba nigaare khuubrooye
Tapad aan zamaan dile man paye khuubtar nigaare
Ze sharer sitaarah jooyam ze sitaarah aaftaabe
Sare manzille nadaaram ki bamieram az qaraare
Chu ze baadah-e bahaare qadah-e kasiedah khezam
Ghazale digar saraayam ba havaa-e nav bahaare
Talabam nihaayate aan ki nihaayate nadaarad
Ba nigaah-e naa shakiebe ba dil umiedvaare
Dile aashqaan bamierad ba bahisht-e jaavidaane
Na navaay-e dardmande na ghame nag ham gusaare

Houri :
Neither you yearn for wine nor you look at me
you know no customs of friendship, how strange!
All you seek is music ever for the heat of desire,
Your soul doles out wine, your verses brim with wine.
With your song you create a world of pleasant garden
Here in paradise I visualize the enchantment of your poesy.

Poet:
You dupe the hearts of wayfarers with your stingy speech,
but joy is never conveyed through the points of those prickles.
No destination in view I have, my nature I cannot stop,
an impatient heart I possess as  breeze in a flower garden.
The moment my eyes rest at the face of a beauteous thing,
the heart is ardent again for some more attractive splendour.
In a spark I search for a star, in star search for the sun,
nowhere I find the end, in rest I find my death.
From a gentle breeze I prepare goblets filled with vintage, 
with every breeze of spring I compose a fresh new song.
I yearn to find the end that has no finite end,
with an insatiable vision, with a heart sated with hope.
The hearts of lovers shall perish in the never-ending paradise
for there is no cry of ache, no grief, and no sharer of grief.

(Tr. S.S.)

Thus for Iqbal, creative activity is essentially an endless, unmotivated groping around for the flashes of truth that are by nature ineffable, but the very longing for attainment is the quintessence of real meaningful being. In Iqbal’s aesthetic framework the power of poetry lies not in the gain of strife, but in unceasing strife itself. Taking the nature as the sine qua non for poetic imagination, Iqbal envisions a genuine poet as essentially homeless, without a permanent locus to have respite from the never-ending engagement. Being always adrift, in the expanse of impersonal material objects, each significant for being a glimmering of the Infinite, is a poet’s job. The Poet’s reply to the Houri reminds us of these lines from Faust’s reply to Worry in Goethe’s Faust (of course without the daemonic intellectuality in Faust’s aesthetic way of life).

A fool! Who thither turns his blinking eyes
And dreams he’ll find his like above in the skies.
Let him stand fast and look around on earth;
Not mute is this world to a man of worth.
Why need he range through all eternity?
Here he can seize all that he knows to be.
Thus let him wander down his earthly day ;
When spirits spook, let him pursue his way;
Let him find pain and his bliss as on he stride,
He ! every moment still unsatisfied.
{Tr. George Madison Priest, 1941.) 

Addressing the Sun, Iqbal produces yet another poetic statement on the nature of the creative quest:

Aarizoo noor-e haqiqat ki hamaare dil main hai
Laila-I zauq-e talab ka ghar is manzil main hai
Kis qadr lazzat kishod-e ‘aqda-e mushkil main hai
Lutf sad haasil hamaare s’ai-e laa haasil main hai.

Longing for the light of Truth lies in our heart,
Laila of yearning has her abode here in this world.
All pleasure lies in resolving the riddle,
Immense pleasure is the reward of the unrewarding strife.

(Tr. S.S.)

In Iqbal’s order of things the poet enjoys the highest pedestal for his/her being the “dieda-I bina-I qaum” a nation’s power of vision.

Mehfil-e nazm-e hakoomat, chahra-e zeba-I qaum
Shair-e rangin nawa hai dieda-e bina-e qaum

In the order of things poets are the beauty of the face of a nation,
A poet with melodious expression is a nations power of vision. 
Jamiel tar hain gul-wa laala faiz se us ke
Nigaah-I shaair-e rangien nawa main hai jaadoo.

All beauteous flowers become prettier because of poets’ grace,
Magic lies in the vision of a melodious poet. 
In his introduction to Muraqqa-i Chughtai of Abdur Rahman Chughtai, Iqbal clearly formulated his notion of the role of poet in society.
The spiritual health of a people largely depends on the kinds of inspiration which their poets and artists receive. But inspiration is not a matter of choice. It is a gift, the character of which cannot be critically judged by the recipient before accepting it. It comes to the individual unsolicited, and only to socialise itself.
Like Mathew Arnold, Iqbal firmly believed that poetry is significant only when it is a criticism of life and an effective medium for the propagation of ennobling ideas and strengthens essential goodness of man. Arnold wrote in his 1880:
More and more mankind will discover that we have to turn to poetry to interpret life for us, to console us, to sustain us. Without poetry, our science will appear incomplete; and most of what now passes with us for religion and philosophy will be replaced by poetry.
In consonance with Arnold’s prophesy, Iqbal also believed that poetry has to play its role without any prejudice of race, political geography and faith. In his introduction to Payaam-I Mashriq he wrote:
… is vaqt dunya main aur bilkhasus mamaaliki mashriq main har aisi kaushis jis kaa maqsad afraad wa aqvaam ki nigah ko jagrafiyaayi hadood se baalaa tar karke an mein ak sahih aur qavi ansaani sierat kie tajdied  yaa tavlied ho , qaabil-I ihtiraam hai.
Tr. Throughout the world, particularly in oriental nations, all such efforts deserve respect as are aimed at reviving or augmenting truthful and powerful human nature.        
It is with this noble aim that poet has to pursue his/her vocation and ceaselessly give went to his soz-e daroon (music within).

Sahar dar shaakhsaare boostaane
Chi khus mi guft murge naghma khwane
Bar aavar har chi andar sienah daarie
Sroode naalai aahe fughane

As dawn is there at work in the garden
And happily birds are rapt in song,
Express whatever lies silent in your bosom,
A song, a wail, a sigh or a cry.

(Tr S.S)