You worship not besides Him except [mere] names you have named them, (12:40)

﴿مَا تَعْبُدُونَ مِن دُونِهِ إِلَّا أَسْمَاءً سَمَّيْتُمُوهَا أَنتُمْ وَآبَاؤُكُم مَّا أَنزَلَ اللَّهُ بِهَا مِن سُلْطَانٍ ۚ إِنِ الْحُكْمُ إِلَّا لِلَّهِ ۚ أَمَرَ أَلَّا تَعْبُدُوا إِلَّا إِيَّاهُ ۚ ذَٰلِكَ الدِّينُ الْقَيِّمُ وَلَٰكِنَّ أَكْثَرَ النَّاسِ لَا يَعْلَمُونَ﴾
[ يوسف: 40]

12:40 You worship not besides Him except [mere] names you have named them, you and your fathers, for which Allah has sent down no authority. Legislation is not but for Allah. He has commanded that you worship not except Him. That is the correct religion, but most of the people do not know.

Joseph told them that they only worshipped names besides Allah, which have not been designated by Allah, but were what they and their ancestors had called gods – yet they had no share in divinity.
Allah had sent no proof showing that giving these names was correct.
The command in all creation is Allah’s alone, and does not belong to these names, which they and their ancestors had come up with.
Allah, glory be to Him, has instructed that you worship Him alone, and has forbidden that you should associate others with Him.
Worshipping Allah alone is the straight path, which has no deviation in it.
Most people do not know this, and therefore they associate other things with Allah, worshipping some of what Allah has created.

"You do not worship besides Him but only names which you have named (forged), you and your fathers, for which Allah has sent down no authority. The command (or the judgement) is for none but Allah. He has commanded that you worship none but Him (i.e. His Monotheism), that is the (true) straight religion, but most men know not.

phonetic Transliteration

Ma taAAbudoona min doonihi illa asmaan sammaytumooha antum waabaokum ma anzala Allahu biha min sultanin ini alhukmu illa lillahi amara alla taAAbudoo illa iyyahu thalika alddeenu alqayyimu walakinna akthara alnnasi la yaAAlamoona

Abdullah Yusuf Ali - Translation

"If not Him, ye worship nothing but names which ye have named,- ye and your fathers,- for which Allah hath sent down no authority: the command is for none but Allah: He hath commanded that ye worship none but Him: that is the right religion, but most men understand not...

Safi-ur-Rahman al-Mubarakpuri

"You do not worship besides Him but only names which you have named (forged) - you and your fathers - for which Allah has sent down no authority. The command is for none but Allah. He has commanded that you worship none but Him; that is the straight religion, but most men know not."

Page 240 English transliteration