Here is an excerpt taken ( for the verse in question ) from the abridged edition of Ibn-Katheer tafseer, by Dar-us-Salam publication, easily regarded by Muslims as one of the best and most popular tafaseer for the Quran:

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The Order to fight People of the Scriptures until They give the Jizyah
Allah said,

﴿قَـتِلُواْ الَّذِينَ لاَ يُؤْمِنُونَ بِاللَّهِ وَلاَ بِالْيَوْمِ الاٌّخِرِ وَلاَ يُحَرِّمُونَ مَا حَرَّمَ اللَّهُ وَرَسُولُهُ وَلاَ يَدِينُونَ دِينَ الْحَقِّ مِنَ الَّذِينَ أُوتُواْ الْكِتَـبَ حَتَّى يُعْطُواْ الْجِزْيَةَ عَن يَدٍ وَهُمْ صَـغِرُونَ ﴾
(Fight against those who believe not in Allah, nor in the Last Day, nor forbid that which has been forbidden by Allah and His Messenger, and those who acknowledge not the religion of truth among the People of the Scripture, until they pay the Jizyah with willing submission, and feel themselves subdued.) Therefore, when People of the Scriptures disbelieved in Muhammad , they had no beneficial faith in any Messenger or what the Messengers brought. Rather, they followed their religions because this conformed with their ideas, lusts and the ways of their forefathers, not because they are Allah's Law and religion. Had they been true believers in their religions, that faith would have directed them to believe in Muhammad , because all Prophets gave the good news of Muhammad's advent and commanded them to obey and follow him. Yet when he was sent, they disbelieved in him, even though he is the mightiest of all Messengers. Therefore, they do not follow the religion of earlier Prophets because these religions came from Allah, but because these suit their desires and lusts. Therefore, their claimed faith in an earlier Prophet will not benefit them because they disbelieved in the master, the mightiest, the last and most perfect of all Prophets . Hence Allah's statement,

﴿قَـتِلُواْ الَّذِينَ لاَ يُؤْمِنُونَ بِاللَّهِ وَلاَ بِالْيَوْمِ الاٌّخِرِ وَلاَ يُحَرِّمُونَ مَا حَرَّمَ اللَّهُ وَرَسُولُهُ وَلاَ يَدِينُونَ دِينَ الْحَقِّ مِنَ الَّذِينَ أُوتُواْ الْكِتَـبَ﴾
(Fight against those who believe not in Allah, nor in the Last Day, nor forbid that which has been forbidden by Allah and His Messenger, and those who acknowledge not the religion of truth among the People of the Scripture,) This honorable Ayah was revealed with the order to fight the People of the Book, after the pagans were defeated, the people entered Allah's religion in large numbers, and the Arabian Peninsula was secured under the Muslims' control. Allah commanded His Messenger to fight the People of the Scriptures, Jews and Christians, on the ninth year of Hijrah, and he prepared his army to fight the Romans and called the people to Jihad announcing his intent and destination. The Messenger sent his intent to various Arab areas around Al-Madinah to gather forces, and he collected an army of thirty thousand. Some people from Al-Madinah and some hypocrites, in and around it, lagged behind, for that year was a year of drought and intense heat. The Messenger of Allah marched, heading towards Ash-Sham to fight the Romans until he reached Tabuk, where he set camp for about twenty days next to its water resources. He then prayed to Allah for a decision and went back to Al-Madinah because it was a hard year and the people were weak, as we will mention, Allah willing.

Paying Jizyah is a Sign of Kufr and Disgrace
Allah said,

﴿حَتَّى يُعْطُواْ الْجِزْيَةَ﴾
(until they pay the Jizyah), if they do not choose to embrace Islam,

﴿عَن يَدٍ﴾
(with willing submission), in defeat and subservience,

﴿وَهُمْ صَـغِرُونَ﴾
(and feel themselves subdued.), disgraced, humiliated and belittled. Therefore, Muslims are not allowed to honor the people of Dhimmah or elevate them above Muslims, for they are miserable, disgraced and humiliated. Muslim recorded from Abu Hurayrah that the Prophet said,

«لَا تَبْدَءُوا الْيَهُودَ وَالنَّصَارَى بِالسَّلَامِ، وَإِذَا لَقِيتُمْ أَحَدَهُمْ فِي طَرِيقٍ فَاضْطَرُّوهُ إِلَى أَضْيَقِه»
(Do not initiate the Salam to the Jews and Christians, and if you meet any of them in a road, force them to its narrowest alley.) This is why the Leader of the faithful `Umar bin Al-Khattab, may Allah be pleased with him, demanded his well-known conditions be met by the Christians, these conditions that ensured their continued humiliation, degradation and disgrace. The scholars of Hadith narrated from `Abdur-Rahman bin Ghanm Al-Ash`ari that he said, "I recorded for `Umar bin Al-Khattab, may Allah be pleased with him, the terms of the treaty of peace he conducted with the Christians of Ash-Sham: `In the Name of Allah, Most Gracious, Most Merciful. This is a document to the servant of Allah `Umar, the Leader of the faithful, from the Christians of such and such city. When you (Muslims) came to us we requested safety for ourselves, children, property and followers of our religion. We made a condition on ourselves that we will neither erect in our areas a monastery, church, or a sanctuary for a monk, nor restore any place of worship that needs restoration nor use any of them for the purpose of enmity against Muslims. We will not prevent any Muslim from resting in our churches whether they come by day or night, and we will open the doors ﴿of our houses of worship﴾ for the wayfarer and passerby. Those Muslims who come as guests, will enjoy boarding and food for three days. We will not allow a spy against Muslims into our churches and homes or hide deceit ﴿or betrayal﴾ against Muslims. We will not teach our children the Qur'an, publicize practices of Shirk, invite anyone to Shirk or prevent any of our fellows from embracing Islam, if they choose to do so. We will respect Muslims, move from the places we sit in if they choose to sit in them. We will not imitate their clothing, caps, turbans, sandals, hairstyles, speech, nicknames and title names, or ride on saddles, hang swords on the shoulders, collect weapons of any kind or carry these weapons. We will not encrypt our stamps in Arabic, or sell liquor. We will have the front of our hair cut, wear our customary clothes wherever we are, wear belts around our waist, refrain from erecting crosses on the outside of our churches and demonstrating them and our books in public in Muslim fairways and markets. We will not sound the bells in our churches, except discretely, or raise our voices while reciting our holy books inside our churches in the presence of Muslims, nor raise our voices ﴿with prayer﴾ at our funerals, or light torches in funeral processions in the fairways of Muslims, or their markets. We will not bury our dead next to Muslim dead, or buy servants who were captured by Muslims. We will be guides for Muslims and refrain from breaching their privacy in their homes.' When I gave this document to `Umar, he added to it, `We will not beat any Muslim. These are the conditions that we set against ourselves and followers of our religion in return for safety and protection. If we break any of these promises that we set for your benefit against ourselves, then our Dhimmah (promise of protection) is broken and you are allowed to do with us what you are allowed of people of defiance and rebellion.'''

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And here is a link for the commentary I quoted:

http://www.alim.org/library/quran/AlQuran-tafsir/TIK/9/28