If you could clarify what the bolded parts mean
Here goes:
1) aaj tu Ghair sahi
pyar se bair sahi
Today you’re a stranger, filled with hatred towards love. However, “ghair” is more nuanced than mere stranger: it is often used for the rival in the stereotypical triangle of love (comprising the lover, the beloved and the rival for the beloved’s affections). Here it signifies someone who was once the poet/protagonist’s, but now is someone else’s. Likewise, “bair” isn’t simply hatred. It is hatred of a vehement, visceral sort.
2) pyar ki aag main
sangdil mein jala hoon jitna
tujhko utna na jalaya to mere naam nahine
Poor guy has been burning in the fire of love, and vows that if he doesn’t make the lady burn just as much in that fire, she can change his name, which is an oft-used figure of speech in Urdu: recall please Shahbaz Sharif insisting he would get rid of load shedding in two years and if he didn’t, we could change his name.
3) saari duniya mein fakat
tujhse muhabbat ki hai
In this entire world, I’ve loved you alone.
4) naaz hai tujhko bahoth
husn pe apne lekin
tere sar ko na jhukaya to mera naam nahin
You pride yourself on your beauty, but I will make you bow in submission, or else, you guessed it, you’re free to change my name. Something tells me this guy wouldn’t really mind a new name. Seriously though, “naaz” here is more than mere pride. Naaz is the pride a lady feels and the airs she adopts when she knows her beauty has admirers.
5) hai yakin mujhko ke magroor jawani teri
mom banke meei bahon main simat aayegi
I’m certain that your arrogant youth will melt into my arms like so much wax. Poets often portray icy cold, haughty beauty melting. Faiz does so too at one point, but his verse escapes me right now. The idea is again making the recalcitrant beloved submit under the pressure of your attention. In the #MeToo era, such poetry probably hasn’t aged well.
6) sangemarmar se hasine
tere badan pe sangdil
lal joda na sajaya to mera naam nahin
Your body is lovely like marble, but if I fail to make you don the red bridal dress on that very body, you can... (drumroll)... change my name.
