In several of his Hadiths (wise sayings), the Prophet Muhammad encouraged people to demonstrate their belief in Allah by their actions to their neighbors. In his view, those who lived a good life – honest and respectful of sh3er, were aligned with Allah.
He frowned upon those who mistreated their neighbors and denied their claim of being true believers saying,

“I swear by Allah he is not a believer, I swear by Allah he is not a believer and I swear by Allah he is not a believer.”

 After he repeated it three times, his companions asked him, who the ‘he’ was that he referenced and he replied,

“The one whose neighbors are unsafe because of his mistreatment.”

 Those who practice the Islamic faith are expected to be good neighbors. Good neighbors care about each other and look out for each other’s interests. They will visit each other every now and then, exchange small gifts on occasion, offer support to each other in times of illness, offer consolation to each other in difficult times and be ready to support and assist each other when needed.
 In the Noble Quran (An-Nisaa Surah: 36), Allah (Allah) specifically recommends that neighbors treat each other with respect and kindness:

“And serve Allah. Ascribe no thing as partner unto Him. (Show) kindness unto parents, and unto near kindred, and orphans, and the needy, and unto the neighbor who is of kin (unto you) and the neighbor who is not of kin, and the fellow-traveler and the wayfarer and (the slaves) whom your right hands possess. Lo! Allah loves not such as are proud and boastful, (36)”
There is a story about Muhammad’s life which helps to demonstrate the importance of giving time and care to your neighbor: One day, the Prophet stood with a man at length, talking.
One of the Prophet’s companions saw the man and thought he was taking too much time with the prophet and talking too much. Thus, when the prophet Muhammad finished talking to the man and he had walked away, his companion came to him saying, “I nearly came to ask that man to move away. I felt he was bothering you with his talk.”

 The prophet replied,
 “Do you mean the man that was standing with me earlier?” The man nodded yes. Then the prophet explained that the man with whom he had been speaking was the angel Jibril (Gabriel) who had come to explain a very important teaching. He said that the angel Jibril carried a message from Allah and Allah wanted people to understand that their actions on this earth, in particular, their treatment of people here on this earth, especially their neighbors, will ultimately determine how they are judged in the end. The angel Gabriel urged the Prophet shared this message with the people on earth because on judgment day, the way they have behaved towards their neighbor will determine whether they will enter Paradise or not.
Below are some of the prophet’s Muhammad’s famous Hadiths that describe the importance of respecting one’s neighbors and treating them with kindness:

“Anyone mistreating one’s neighbors shall never enter paradise.”

“Whosoever wants to be a true believer in Allah, he or she shall treat their neighbors well, shall honor his or her guest and shall speak only what is good or else keep silent.”

“I swear by Allah he is not a believer, he who eats to his fullness knowing his neighbor is hungry.”

 In reading the Hadiths one comes to understand the importance of caring for sh3er and treating them with respect, dignity and love.
 In Islam, people are encouraged to share with their neighbors, when they are making a meal they are encouraged to make enough to share with sh3er. The prophet said in this regard to one of his companions (Abu Thar),

“If you cook food at home, then make it in a large quantity so you can give some to your neighbors.”

 The prophet Muhammad also encouraged people to be grateful for any gift received from a neighbor, regardless of its size.
 Also as a Muslim, if you are considering selling your home, before you put it on the market for sale, you ought to first offer it to your neighbors as one of them may be interested in buying it and he should be given priority.
 Under Islamic law, neighbors are directed to protect the interests of their neighbors, whether it’s social or financial interests.

The Prophet Muhammad once asked his companions, “What do you think of adultery?” They said, “It is forbidden.” And he replied, “If one commits adultery with a neighbor’s wife, daughter or sister, it is ten times more punishable by Allah than committing this bad act with a stranger.”
Then he asked again, “What do you think of robbery?” They said, “It is forbidden.” And he replied, “If one robs his neighbor’s house it is ten times more punishable by Allah than robbing any other house.”

 He was demonstrating that committing these offences against someone you know is far worse than committing them with a stranger since there is an implied ‘trust’ among those you know and interact with regularly.
 Prophet Muhammad warned that those who mistreated their neighbors would be dealt with harshly because, in essence, when they mistreat their neighbor - they are mistreating
Allah:

“He who harms his or her neighbors it is as if he or she has harmed me. And he or she who harms me, it is as if he or she has harmed Allah".

 Furthermore, he or she who fights with his or her neighbors, it is as if he or she has fought with me, and he or she who has fought with me it is as if he or she has fought with Allah.”
 There are comprehensive rules in Islam defining what constitutes good treatment of neighbors, on more than one occasion the Prophet spoke to his companions about the expectations. In general one is expected to treat one’s neighbor as he himself would want to be treated - to assist when assistance is required; to support when called upon for
support; to take care to check-in when one is sick; to congratulate when there is reason for joy and celebration; to console when there is trouble and difficulties; to share in their sorrows and to never raise your building next to his in such a way that it blocks the sun and wind from reaching his home.
 In Islam a bad neighbor is considered one of the three most devastating kinds of people, as per the Prophet Muhammad’s Hadith:

“The three devastating kinds of people are: the unjust boss, who when seeing good never gives thanks and when seeing bad never forgives; the bad neighbor who when he sees a good act just passes over it and when he sees a bad act spreads news about it quickly through gossip; and the bad wife who teases you when you stay with her and cheats on you if you leave her at home.”