وَلاُضِلَّنَّهُمْ

Verily, I will mislead them,

from the true path,
 
وَلاُمَنِّيَنَّهُمْ

and surely, I will arouse in them false desires;

tempting them to feign repentance, arousing false hopes in them, encouraging them to delay and procrastinate with righteous deeds, deceiving them.
 
وَلامُرَنَّهُمْ فَلَيُبَتِّكُنَّ اذَانَ الَانْعَامِ

and certainly, I will order them to slit the ears of cattle,

Qatadah and As-Suddi stated,

meaning, slitting their ears to designate them as Bahirah, Sa'ibah, and a Wasilah.
 
وَلامُرَنَّهُمْ فَلَيُغَيِّرُنَّ خَلْقَ اللّهِ

And indeed I will order them to change the nature created by Allah.

According to Al-Hasan bin Abi Al-Hasan Al-Basri,

means tattooing. 

In his Sahih, Muslim recorded the prohibition of tattooing the face, which in one of its wordings states:

"May Allah curse whoever does this."

It is also recorded in the Sahih that Ibn Mas`ud said,

"May Allah curse those who have tattoos and those who do it, who pluck their (facial) hairs and the one who does it for them, and those who make spaces between their teeth for the purpose of beauty, changing what Allah has created."

He then said,

"Why should not I curse whom the Messenger of Allah has cursed, when the Book of Allah commands it," referring to the Ayah,

وَمَأ ءَاتَـكُمُ الرَّسُولُ فَخُذُوهُ وَمَا نَهَـكُمْ عَنْهُ فَانتَهُواْ

And whatsoever the Messenger gives you, take it; and whatsoever he forbids you, abstain (from it). (59:7) 

Allah's statement,
 
وَمَن يَتَّخِذِ الشَّيْطَانَ وَلِيًّا مِّن دُونِ اللّهِ فَقَدْ خَسِرَ خُسْرَانًا مُّبِينًا
 
 

And whoever takes Shaytan as a Wali (protector or helper) instead of Allah, has surely suffered a manifest loss.

means, he will have lost this life and the Hereafter.

Indeed, this is a type of loss that cannot be compensated or restored.

Allah's statement,

يَعِدُهُمْ وَيُمَنِّيهِمْ وَمَا يَعِدُهُمُ الشَّيْطَانُ إِلاَّ غُرُورًا