They are not [all] the same; among the People of the Scripture (3:113)

﴿۞ لَيْسُوا سَوَاءً ۗ مِّنْ أَهْلِ الْكِتَابِ أُمَّةٌ قَائِمَةٌ يَتْلُونَ آيَاتِ اللَّهِ آنَاءَ اللَّيْلِ وَهُمْ يَسْجُدُونَ﴾
[ آل عمران: 113]

3:113 They are not [all] the same; among the People of the Scripture is a community standing [in obedience], reciting the verses of Allah during periods of the night and prostrating [in prayer].

Having made clear what many of the People of the Scripture are like, Allah then explains that there is a group among them who are upright and stand by the truth – not all the People of the Scripture are the same.
Rather, there is a group among them who follow the Religion of Allah: doing as Allah instructs and staying away from what He has prohibited, reading the verses of Allah in the hours of the night, and praying to Him.
This group existed before the Prophet Muhammad ( peace be upon him ) was sent, and became Muslim when they met him and understood his message.

Not all of them are alike; a party of the people of the Scripture stand for the right, they recite the Verses of Allah during the hours of the night, prostrating themselves in prayer.

phonetic Transliteration

Laysoo sawaan min ahli alkitabi ommatun qaimatun yatloona ayati Allahi anaa allayli wahum yasjudoona

Abdullah Yusuf Ali - Translation

Not all of them are alike: Of the People of the Book are a portion that stand (For the right): They rehearse the Signs of Allah all night long, and they prostrate themselves in adoration.

Safi-ur-Rahman al-Mubarakpuri

Not all of them are alike; a party of the People of the Scripture stand for the right, they recite the verses of Allah during the hours of the night, prostrating themselves in prayer.

Page 64 English transliteration