Can you please give me the idea of sunnah dress in indo pak subcontinent some people claim that panjabi is sunnah dress and shirt is kafir's dress and whoever wears shirt is a fasiq but after some inspection I found that panjabi is the traditional dress of hindus . You will find in the festivals of hindus they wear panjabi.From a hadith in Shahi al bukhari I know that prophet tried to refrain from mushrik's culture and in follow ahli kitab's culture. Although in some narrations of bukhari it is found that he forbade us to refrain from Ahl-i-kitab. And there are many difference in dresses. So, far I know arabs wear long robe no arab wear panjabi. Then how come panjabi a sunnah dress? Sometimes , the dresses of arab goes beyond the ankle then surely, it becomes haram. At the same time you will find a lot of differences in the dress of African muslims and Turkish muslims. Then what is the sunnah dress? At the same time I think we must refrain from the opinion that panjabi is sunnah dress because it is the dress of hindus and they are more evil than Ahli kitab (While Ahli kitab wear shirt).

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

In principle all clothes are permissible unless there is evidence from the Book of Allaah and the Sunnah of the Prophet that a given garment is forbidden. Allaah Says (what means): {It is He who created for you all of that which is on earth.}[Quran 2:29].

However, there is evidence from Islamic texts that some kinds of clothes are forbidden:

1-     Silk is forbidden for men, and any clothes which contain images of living creatures are forbidden for men and women.

2-     It is forbidden to wear see-through or tight clothes which shape the 'Awrah (parts of the body that must be covered in Islam) for men and women.

3-     It is forbidden for men to wear clothes by which they imitate women, and it is forbidden for women to wear clothes by which they imitate men.

4-     It is forbidden to wear clothes by which one imitates the non-Muslims, whether the people of the Book or other polytheists; that is to say wearing clothes that are peculiar to them and which are not commonly worn by others.

5-     It is forbidden to wear fashion clothes or clothes that are different from the clothes which the people in that country are accustomed to.

In principle, it is permissible to wear clothes that do not fall in any of the above mentioned types, whether in the Indian sub-continent or anywhere else.

Saying that the Panjabi dress worn by Muslims in Pakistan and Afghanistan is a dress peculiar to the non-Muslims because the Hindus wear it in their celebrations is not correct. One imitates the non-Muslims only if he wears the clothes that are peculiar to them, and there is no doubt that the Panjabi dress is not peculiar to the non-Muslims or Hindus, rather it is a symbol of the Muslims to an extent that it is attributed to them, as people say 'a Panjabi dress' or 'an Afghan dress'. Therefore, wearing this dress is a practice by Muslims, by which they distinct themselves from others. For more benefit, please refer to Fatwa 84622.

As regards your statement that the Prophet tried to resemble the people of the Book, then it should be noted here that this was at the very beginning when there were very few Arab Muslims, but when Islam spread among the Arabs, the Prophet did not imitate them; on the contrary, he ordered the Muslims to distinct themselves from the non-Muslims.

Az-Zarqaani when explaining the book of Imaam Maalik [Al-Muwatta'], said: "The last of the two orders [of the Prophet ordering to imitate the Jews and then finally ordering to differ from them] was when most of the idol worshippers embraced Islam and the Jews insisted on their rejection to Islam, and calling them to Islam was of no avail, then the Prophet ordered the Muslims not to imitate them in many matters, like his  order to dye our hair because the Jews and the Christians do not dye their hair."

Allaah Knows best.