The Seventh Characteristic
وَالَّذِينَ لَا يَدْعُونَ مَعَ اللَّـهِ إِلَـٰهًا آخَرَ (And those who do not invoke any other god along with Allah - 25:68). The first six characteristics included the principles of obedience and now the characteristics of disobedience are described. Among these the very first one relates to belief, that is these blessed servants do not associate any one with Allah Ta’ ala in His worship. This point establishes that shirk (شِرک) is the biggest sin of all.
The Eighth and Ninth characteristic
لَا يَقْتُلُونَ النَّفْسَ الَّتِي حَرَّمَ اللَّـهُ (do not kill a person whom Allah has given sanctity - 25:68). This is the description of the major and grave sins pertaining to one's deeds. It is mentioned that Allah's blessed servants do not go even near them; neither they indulge in adultery nor do they kill innocent people. After describing the beliefs and big sins of one's deeds the verse says وَمَن يَفْعَلْ ذَٰلِكَ يَلْقَ أَثَامًا (25:68) that is, whoever will involve himself in the above mentioned sins will get punished accordingly. Abu Ubaidah has described the meaning of the word اَثَام (atham) in this verse as punishment of sin. But some other commentators have said that اَثَام is the name of a valley in the Hell which is full of severe and rigorous punishments, and they have quoted a few sayings in support of this contention. (Mazhari)