What is the role of religion in human life with special reference to Sikhi?

The goal of human life according to some is the attainment of perfection, and according to others, it is the acquisition of happiness. Pleasure-seeking and fleeting joys should not be mistaken for happiness. Religion is the key to real happiness because it produces harmony by an integrated development of human personality and control of impulses, desires and thoughts. There can be no rigid approach for a human being as the problems of each individual are peculiar. Religion has to be flexible to suit the need of individual development.
Religion is the realization of a “Divine presence” within oneself while leading a normal life. If divinity, progress and truth are not realized in human existence then the very purpose of man’s life is defeated. True religion implies a search for the Truth and flexibility, in the individual approach to spiritual matters. Myths, forms and systems have fossilized religion and destroyed ‘The Truth’ and vitality in it.
Guru Nanak felt that spiritual development should not be crushed by outward symbols and forms. To bind the soul to the wheels of a socio-religious machinery is a type of spiritual slavery. Freedom of the soul is vital for its adjustments to the needs of life and the complexity of social organization. Constant adaptation is necessary for the achievement of harmony, between the individual and the Supreme Being. Man’s nature is extremely complex and it is suicidal to chain it to a rigid groove or pattern.
Guru Nanak discarded all the prevalent superstitions of traditional forms of worship and symbols. He pointed out the absurdity of idolatry, hypocrisy, caste exclusiveness and pilgrimage. He challenged the use of intoxicants and narcotics, and the practice of Sati and infanticide. At the same time, he advocated the maintenance of ethical values in daily life: justice, truth, honesty, humility, fearlessness and gratitude. These qualities make a man a true citizen of the world.

Guru Nanak Ji shows the way to save the world. Guru Amar Das Ji says:
ਸਲੋਕ ਮ: ੩ ॥
ਜਗਤੁ ਜਲੰਦਾ ਰਖਿ ਲੈ ਆਪਣੀ ਕਿਰਪਾ ਧਾਰਿ ॥
ਜਿਤੁ ਦੁਆਰੈ ਉਬਰੈ ਤਿਤੈ ਲੈਹੁ ਉਬਾਰਿ ॥
ਸਤਿਗੁਰਿ ਸੁਖੁ ਵੇਖਾਲਿਆ ਸਚਾ ਸਬਦੁ ਬੀਚਾਰਿ ॥
ਨਾਨਕ ਅਵਰੁ ਨ ਸੁਝਈ ਹਰਿ ਬਿਨੁ ਬਖਸਣਹਾਰੁ ॥੧॥
“Shalok, Third Mehl:
The world is going up in flames – shower it with Your Mercy, and save it!
Save it, and deliver it, by whatever method it takes.
The True Guru has shown the way to peace through contemplating the True Word of the Shabad.
Nanak knows no other than the Lord, the Forgiving Lord. ||1||”
(Ang 853)