Surah Al A'raf Tafseer

الَّذِينَ يَصُدُّونَ عَن سَبِيلِ اللّهِ وَيَبْغُونَهَا عِوَجًا

Those who hindered (men) from the path of Allah, and would seek to make it crooked,

meaning, they hindered the people from following Allah's path, His Law, and what the Prophets brought. They sought to make Allah's path appear crooked and winding, so that no one would follow it.

Allah said,

وَهُم بِالاخِرَةِ كَافِرُونَ

and they were disbelievers in the Hereafter.

They disbelieved in the Meeting with Allah in the Hereafter, They used to deny this will ever occur, not accepting it nor believing in it. This is why they used to discount the seriousness of the evil deeds and statements that they committed, because they did not fear any reckoning or punishment. Therefore, they were and are indeed the worst people in statement and action