One of the most popular ghazal of Mehdi Hasan. Its written by Tasleem Fazli.

rafta rafta woh meri hasti ka samaan ho gaye
pehle jaan phir jaan-e-jaan fer jaan-e-jaana ho gaye

din-ba-din badti gai us husan ki raanaiyan
 pehle gul fir gul-badan fir gul-badaama ho gaye
rafta rafta woh meri hasti ka samaan ho gaye
(raanai=beauty)

aap to nazdik se nazdik-tar aate gaye
pehle dil fir dil-ruba fir dil ke mehmaan ho gaye
rafta rafta woh meri hasti ka samaan ho gaye