Everyone is safe from the believer
The Prophet (peace and blessings of Allah be upon him) said: “The Muslim is he whom the people are safe from harm of his hand and tongue.” Al-Bukhari
The hadith is not specific to the way a Muslim treats a believer or a non believer. There is no stipulation about who is mentioned, the good treatment is general to everyone. But people note there are different versions of this hadith. One saying Muslim, one people and one saying believer.
Some do translate it as Muslims but the word used is people. Are not people made of believers and non believers? Now that you agree you can see the far reaching meaning of this one hadith. People, whoever they are, should be safe from any harm from the Muslim. One Muslim cannot harm another Muslim because this of the bond of belief. In terms of the non believer, he has to be good to him, how else will that person come to Islam? Good character is one of the ways that a person enters into Islam. So a Muslim has a huge responsibility towards his fellow man, regardless of their faith.
After the conquest of Mecca, Wahshi came to the Prophet (peace and blessings of Allah be upon him) accepted Islam then someone recognised that he was the killer of Hamza (may Allah be pleased with him). He (peace and blessing of Allah be upon him) said, “Let him be.” “For one man’s Islam is dearer to me than the slaying of a thousand disbelievers.” (Martin lings Sira p.323)
Look how the Prophet (peace and blessings of Allah be upon him) has complete control of his being and anger. Then look how the slayer of his beloved uncle is absolutely safe with him because he has become Muslim.
A Muslim should never lie
Lying is something that anyone who knows anything is bad. We all know how bad lying is, so we do we do it?
Abu Darda (may Allah be pleased with him) said, “O’ Messenger of Allah, can a believer lie?” He said, “No. No believer in Allah and the Final day, lies when he speaks.” (Ibn Abi Dunya Makarim Al-Akhlaq p.144)
In a more famous hadith the Messenger of Allah (peace and blessings of Allah be upon him) was asked, “Can a Muslim be cowardly?”
“Can a Muslim be miserly?”
“Can a Muslim lie?”
Some of us do live in societies where lying is a norm and this has to change. Although we may not be able to change those around us, we must change ourselves. Children must be taught that lying is wrong. If we at least do that and that will be a lot.
Musa ibn Shayba reports that, “The Prophet (peace and blessings of Allah be upon him) rejected the testification of a liar.” (Ibn Abi Dunya Makarim Al-Akhalaq p.120)
Do we want our testifications to be rejected? How will people know when a lair is telling the truth? Is that what we want? What will we do on the day of judgement?
When you know you are about to lie, stop yourself and think. Then tell the truth and do not perceive any lie as small or minor. All lies are major wrong actions.