Surah MULK Ayah 9 in Arabic Text:
قَالُوا بَلَىٰ قَدْ جَاءَنَا نَذِيرٌ فَكَذَّبْنَا وَقُلْنَا مَا نَزَّلَ اللَّهُ مِنْ شَيْءٍ إِنْ أَنْتُمْ إِلَّا فِي ضَلَالٍ كَبِيرٍ
Qaaloo balaa qad jaaa’anaa nazeerun fakazzabnaa wa qulnaa maa nazzalal laahu min shai in in antum illaa fee dalaalin kabeer
DR. GHALI They say, “Yes indeed, a Warner has already come to us; yet we cried lies and said, ?In no way has Allah been sending down anything whatever; decidedly you are in (nothing) except a great error.”
MUHSIN KHAN They will say: “Yes, indeed a warner did come to us, but we belied him and said: ‘Allâh never sent down anything (of revelation); you are only in great error.’”
PICKTHALL They say: Yea, verily, a warner came unto us; but we denied and said: Allah hath naught revealed; ye are in naught but a great error.
SAHIH INTERNATIONAL They will say, “Yes, a warner had come to us, but we denied and said, ‘Allah has not sent down anything. You are not but in great error.'”
MUFTI TAQI USMANI They will say, “Yes, a warner had come to us, but We had rejected, and said, ‘Allah has not revealed anything. You are only in great error.’”
ABDUL HALEEM They will reply, ‘Yes, a warner did come to us, but we did not believe him. We said, “God has revealed nothing: you are greatly misguided”.
ABUL ALA MAUDUDI They will say: “Yes, a warner came to us, but we gave the lie to him and said: ‘Allah has revealed nothing. You are surely in huge error.’
DR. MUSTAFA KHATTAB They will reply, “Yes, a warner did come to us, but we denied and said, ‘Allah has revealed nothing. You are extremely astray.’”
Surah Mulk Ayat 9 Tafseer / Commentary
Here you can expand your knowledge on ayah 9 of Surah Mulk by reading both the tafsir of Ibn Kathir and Abul Ala Maududi.
This section is for those looking to find explanation of verse 9 and gain more insight to the background or significance of this verse.
Tafsir of Surah Mulk Ayat 9 – By Abul Ala Maududi
(67:9) They will say: “Yes, a warner came to us, but we gave the lie to him and said: ‘Allah has revealed nothing. You are surely in huge error.’ 
15. That is, not only you but the people who have believed in and followed you also are misguided and lost in grave error.
Surah Mulk Tafsir by Ibn Kathir – Ayat 6-11
The tafsir of ayat 6-11 of Surah Mulk is provided on this page.