Iman, or faith, is one of the essential pillars of Islam. Without faith, a Muslim cannot hope to gain salvation in the hereafter. Iman is not simply a matter of believing in the existence of Allah – it is also about having faith in His prophets, His angels, His holy books, the Day of Judgment, and believing in destiny, both the good and the bad.

Iman is essential to a Muslim’s relationship with Allah. It is through faith that a Muslim can hope to gain Allah’s mercy and forgiveness. Faith also allows a Muslim to lead a good and righteous life by Allah’s will.

The importance of iman is emphasized in the Quran as well. For example, in Surah al-Baqarah, Allah says:

5 important things to remember about Iman:

• Iman is faith or belief in Allah. 
• Iman is one of the five pillars of Islam.
• Iman is required for a Muslim to enter Paradise. 
• Iman can increase or decrease depending on a person's deeds.
• Iman can be lost if a person commits serious sins or leaves Islam.
  

As mentioned above, Iman can increase or decrease. For example, iman can decrease if a person stops performing good deeds, if they stop believing in Allah, or if they start committing sins. AndIman can be increased through acts of worship, such as prayer, and by doing good deeds. Additionally, gaining knowledge about Islam and reflecting on one's faith can help increase Iman.

Clearly, iman is of utmost importance in Islam. Those who have true faith in Allah and His messenger Muhammad (peace be upon him) will be richly rewarded in the hereafter.

Allah knows best, may He grant all of us understanding.