Tafsir of Al-Ma'idah 5:81

ولو كانوا يومنون بالله والنبي وما أنزل إليه ما اتخذوهم أولياء

And had they believed in Allah, and in the Prophet and in what has been revealed to him, never would they have taken them as friends. meaning, had they sincerely believed in Allah, His Messenger and the Qur'an, they would not have committed the evil act of supporting the disbelievers in secret and being enemies with those who believe in Allah, the Prophet and what was revealed to him,

ولكن كثيرا منهم فاسقون

but many of them are rebellious. disobedient to Allah and His Messenger and defiant of the Ayat of His revelation that He sent down