Other than our family members and relatives, the closest people to us are our neighbors. As such, upholding and respecting the rights of our neighbors is one of the most important obligations and duties for Muslims.
Generally, we are mindful of the role and importance of our parents, elders and relatives in our lives. However, we often forget about the people living next door to us; we often overlook the rights of our own neighbors.
Treating our neighbors with respect and kindness is Sunnah, and as true Muslims, our behavior towards our neighbors should be that of solidarity and kindness.
Ibn Umar (RA) and Hz Aisha (RA) reported: 
Prophet Muhammad (PBUH) said: “Gabriel kept on recommending me about treating the neighbors in a kind and polite manner, so much so that I thought that he would order (me) to make them (my) heirs.”
In fact, goodness towards one’s neighbor is enshrined in the Shariah itself, and is considered to be an integral part of one’s faith. Narrated Abu Shura’ih (RA): 
The Prophet (PBUH) said: “By Allah, he does not believe! By Allah, he does not believe! By Allah, he does not believe!” It was said: “Who is that, O Allah’s Messenger (PBUH)?” He said: “That person whose neighbor does not feel safe from his evil.”
In Islam, the neighbor has many rights, some of which are:
- Returning his greetings and accepting his invitations
- Refraining from harming him
- Bearing the harm of the neighbor
- Helping him accomplish his rightful needs
- Concealing his secrets and guarding his honor.
Furthermore, a good Muslim should:
- Visit his neighbor if he is ill
- Escort his funeral if he dies
- Support him if he is oppressed
- Prevent him from wrongdoing and disobedience as much as possible
- Console and give him generously
- Help him in times of distress
- Offer solace to him in times of misfortune
- Congratulate him in times of happiness
- Offer honest advice to him and his family
- Exhort him kindly if he is ignorant about important affairs
- Take care and keep an eye on his house if he is absent
- Respect his privacy and personal space.
Therefore, as Muslims, we should be aware of our duties towards our neighbors, and be willing to extend a helping hand in times of need. As narrated by Ibn Abbas (RA) to Ibn az-Zubayr (RA): 
I heard the Prophet, may Allah bless him and grant him peace, say: “A man is not a believer who fills his stomach while his neighbor is hungry.”
- Sahih Bukhari Vol 08, Book 73, Hadith 44
- Sahih Bukhari Vol 08, Book 73, Hadith 45
- al-Adab al-Mufrad Book 06, Hadith 112