لبیک

'Labbaik' means 'Here I am, I answer your call.' This is the phrase pilgrims cry at Hajj. Iqbal is saying: I answer the call of my heart's deepest longing. I have seen you, recognized you, come to know you.

For your sake I passed through the whole world, and by becoming yours I found everything. This means: when you give yourself completely to love (or to God), you gain everything.