[Human beings were created with an internal drive to seek out purpose and to live for something greater than themselves. Many people have the misfortune of living for the sake of something in the world, devoting their lives to the transient, worshipping created objects instead of the Creator. They do not acknowledge where they came from, why they are here, and where they will end up after their inevitable death. Lost and without guidance, they stumble through life until the Reality confronts them.
But many of them want direction in their lives and conviction in the knowledge of the Hereafter. They only need to be shown the path, the universal and primordial religion revealed to the Prophets and Messengers, Islam, peaceful surrender to the Will of the Creator.

In Islam, we have a clear conception of why we were created, what constitutes righteous living, and what happens after death. Moreover, Islam is not simply a set of rules and beliefs, but also contains the seeds of constant self-improvement. We have been taught how to grow closer and closer to the Creator, to become excellent worshippers and moral leaders, to the point that our individual will and the eternal Will of the Creator become perfectly aligned. This is known to us as the station of Iḥsān, religious excellence, the very top of the spiritual mountain.

The three levels of our religion were revealed to the Prophet Muḥammad ﷺ in the famous hadith about his encounter with the Angel Gabriel, upon him be peace. Gabriel came to the Prophet ﷺ while he was surrounded by his companions and he said, “O Muḥammad, tell me about Islam.” The Prophet ﷺ said:
Islam is to testify there is no true god but Allah and Muḥammad is the Messenger of Allah, to establish prayer, to give charity, to fast the month of Ramadan, and to perform the Hajj pilgrimage to the House if one can find a way.

Gabriel said, “You have spoken truthfully,” and then he said, “Tell me about faith.” The Prophet ﷺ said:
Faith is to believe in Allah, His angels, His books, His messengers, the Last Day, and to believe in the Divine Decree (al-qadr), both its good and its evil.

Gabriel said, “You have spoken truthfully, so tell me about excellence.” The Prophet ﷺ said:
Excellence is to worship Allah as if you see Him, for though you do not see Him, He surely sees you.

This narration lays out the journey before us, from religious infancy to spiritual maturity: surrender, faith, and excellence. When each of these terms is used in isolation, they refer to the totality of faith. When they are contrasted, they each have a specific meaning. Imām Ibn Taymiyyah explains the hadith, writing:
The hadith of Gabriel clarifies that Islam is built upon five pillars, which is Islam itself. It is not based upon anything other than its foundation. Rather, the Prophet ﷺ designated three degrees of the religion. The pinnacle is excellence (al-iḥsān), its middle is faith (al-īmān), and its base is Islam. Thus, every good-doer (muḥsin) is a believer and every believer is Muslim, but not every believer is a good-doer and not every Muslim is a believer.]

reference: https://yaqeeninstitute.org/read/paper/islam-iman-ihsan-climbing-the-spiritual-mountain