What are the qualities that a man must possess; is strictness one of them, and how does one acquire it?

Muslim men and women must act according to what Allah has ordained and embody the characteristics He loves, while shunning what He dislikes. Among the important traits are mercy, gentleness, and kindness. Allah described His Messenger as: "So by mercy from Allah, [O Muhammad], you were lenient with them. And if you had been rude [in speech] and harsh in heart, they would have disbanded from about you," and "to the believers he is kind and merciful." The Prophet, peace and blessings be upon him, said: "Those who show mercy will be shown mercy by the Most Merciful. Show mercy to those on earth and the One in the heavens will show mercy to you." Among the ethical principles are courage, generosity, wisdom, justice, understanding, and helpfulness. Severity is sometimes required, such as in striving against disbelievers and hypocrites, and in applying punishments (hudud) without leniency, as in His, the Almighty's, saying: "Strong against the disbelievers, merciful among themselves." And the implementation of the Hadd (prescribed punishment) is a mercy from Allah to His servants, so the ruler should be firm in its implementation.