Why was the Quran revealed in Arabic?

The following reasons have been given in the Qur'an for its revelation in Arabic language:

1. Arabic was the language of the people where it was revealed

وَكَذَلِكَ أَوْحَيْنَا إِلَيْكَ قُرْآنًا عَرَبِيًّا لِتُنْذِرَ أُمَّ الْقُرَى وَمَنْ حَوْلَهَا وَتُنْذِرَ يَوْمَ الْجَمْعِ لا رَيْبَ فِيهِ فَرِيقٌ فِي الْجَنَّةِ وَفَرِيقٌ فِي السَّعِيرِ

"And thus: We have revealed to you a Qur'an in Arabic so that you may warn the Foremost of all towns and those who dwell around it, and may warn of the Day of Gathering, which is beyond all doubt. One group will be in the Garden, and one group will be in the Flames." [42:7]

2. To explain it without any want of clarity, distinctness or perspicuousness

وَلَوْ جَعَلْنَاهُ قُرْآنًا أَعْجَمِيًّا لَقَالُوا لَوْلا فُصِّلَتْ آيَاتُهُ أَأَعْجَمِيٌّ وَعَرَبِيٌّ قُلْ هُوَ لِلَّذِينَ آمَنُوا هُدًى وَشِفَاءٌ وَالَّذِينَ لا يُؤْمِنُونَ فِي آذَانِهِمْ وَقْرٌ وَهُوَ عَلَيْهِمْ عَمًى أُولَئِكَ يُنَادَوْنَ مِنْ مَكَانٍ بَعِيدٍ

"Now if We had made it a Qur'an in a non-Arabic tongue they would surely have said, "Why is it that its verses have not been made clear? Why - a foreign tongue and an Arab?" Say, "For those who accept it, this is a Guidance and medicine for a wholesome life. But as for those who will not believe (Arabs or non-Arabs), in their ears is deafness, and so it remains obscure to them. They are like people who are called to from afar." [41:44]

3. To make it easy to understand

  إِنَّا أَنْزَلْنَاهُ قُرْآنًا عَرَبِيًّا لَعَلَّكُمْ تَعْقِلُونَ

"Behold, We have sent it down in all clarity, in the Arabic tongue, so that you might encompass it with your reason." [12:2]

  إِنَّا جَعَلْنَاهُ قُرْآنًا عَرَبِيًّا لَعَلَّكُمْ تَعْقِلُونَ

"Behold, We have made it a Qur'an in clear Arabic language that you may fully understand." [43:3]

Arabic was the most advanced and comprehensive language at the time when Qur'an was being revealed and it still is the most comprehensive. The terms, concepts and themes would be best clarified and explained in Arabic language and last but not the least, it was the language of the people where it was revealed.