Anas b. Malik reported: The Messenger of Allah (ﷺ) said: I will come to the gate of Paradise on the Day of Resurrection. and would seek its opening. and the keeper would say: Who art thou? I would say: Muhammad. He would then say: It is for thee that I have been ordered, and not to open it for anyone before thee.
Source: sunnah.com
Other translations
Arabic
وَحَدَّثَنِي عَمْرٌو النَّاقِدُ، وَزُهَيْرُ بْنُ حَرْبٍ، قَالاَ حَدَّثَنَا هَاشِمُ بْنُ الْقَاسِمِ، حَدَّثَنَا سُلَيْمَانُ بْنُ الْمُغِيرَةِ، عَنْ ثَابِتٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " آتِي بَابَ الْجَنَّةِ يَوْمَ الْقِيَامَةِ فَأَسْتَفْتِحُ فَيَقُولُ الْخَازِنُ مَنْ أَنْتَ فَأَقُولُ مُحَمَّدٌ . فَيَقُولُ بِكَ أُمِرْتُ لاَ أَفْتَحُ لأَحَدٍ قَبْلَكَ " .
sunnah.com