Nadira Zaheer Babbar declares that there has been no finer qawwali written in Hindi films than Sahir Ludhianvi’s Yeh ishq ishq hai in Barsaat Ki Raat (1960). It’s a very long piece (composed by Roshan), but as a sample there are the lines:

Mazhab-e-ishq ki har rasm kadi hoti hai,
Har qadam par koi deewaar khadi hoti hai
Ishq aazad hai, Hindu Na Musalmaan hai ishq,
Aap hii dharm hai aur aap hii imaan hai ishq
Jis se aage nahin sheikh-o-Brahaman donon,
Us haqeeqat ka garajtaa hua ailaan hai ishq