Does Islam develop and reinforce the spiritual side in man?
Spirit is from the world of divine perfection, so it tends to its origin. It tends to be near God and enjoy holy words revealed by God. It feels happy when listening to what makes it obedient to God. It gets pleased when being in a place where God is remembered.
It is attracted when mentioning high degrees and superior positions near God. It likes to be praised by good manners endeared by God, recommended by the book of God and done by the apostle of God (Blessings and peace of God be upon him).
Islam calls his followers and the believers to all this and urges them to get more and more of this. So Islam for sure reinforces the inside of man and develops his spiritual life as it occupies him by remembrance of God, doing acts of worship for His sake, obeying Him and seeking His proximity.
All the Islamic acts of worship and good manners of belief are just spiritual exercises strengthen man’s intention and develop his internal powers especially if he tastes some spiritual favors and gifts such as seeing true visions while he is asleep, or getting divine inspiration while he is awake, or his internal becomes so clear and pure that he can see by the light of God, or his spirit flies, soars and informed by some hidden divine secrets from God’s highest kingdom.