Guru Nanak preached that the ultimate aim in an individual`s life is to achieve salvation or union with the Lord. In order to accomplish this goal Nanak had given the concept of Sudhana or Discipline which is essentially an effort on the part of an individual to cleanse his or her heart from all negative thoughts. He had said constant meditation with absolute dedication results in cleansing of the human mind and only a clean mind can achieve salvation and union with the Lord. Nanak believed on a special kind of inward devotion in order to achieve salvation. He had focused on six different concepts to explain Sudhana or Discipline. Guru Nanak believed that true religion is expressed within the inner self. Performing only external deeds of religiosity does not guarantee an individual salvation. A person must practice religion with the help of righteous deeds and through the path of Truth, mercy and humility. Nanak had rejected asceticism and had said that the ultimate Truth is living in the world and yet being unaffected by the transient attractions of the World. He had said that True Religion involves purifying ones inner self because an individual whose heart is periled with the darkness of passions can never reach the pinnacle of union with the Lord. Nanak had advised his followers that true religion involves realising the all powerful Lord within the inner self and acting in the path of Truth.
According to Guru Nanak, religion is completely inward and its expression is through love or in a much clearer manner love for the Lord. He had said that love for the formless and incarnate God is necessary for the one who seeks salvation and union with the Lord. A person who bears pure love towards the Almighty finds the grace of the Lord much easily. At the same time Nanak had said that apart from love it is necessary to fear the immensity of God. Unless one fears the immensity of the Lord he or she is not directed towards the Lord. Fear combined with love for the Lord helps an individual to cross the Ocean of Existence. Nanak believed that love for the Almighty is expressed through the Nam Simran or Nam Japan with a pure heart.
Guru Nanak believed that when the heart becomes filled with evil thoughts it is the name of the Lord alone that can bring redemption of the soul. He had said that one should utter the name of God as a part of religion. But uttering the Nam (name) does not merely mean a meaningless repetition of the God`s name without any feeling attached to. The Nam of God should be taken with absolute devotion. Taking the name of God is a way to realise the greatness of the Lord and realisation of all His attributes will guide individuals to lead a life of Truth. When an individual takes the name of God combined with respect, humility, fear, dedication and purity only then can one reap the benefits of his Nam. The rewards of the Nam of the Lord is far reaching because it enables the devotee to seek the grace of the Lord and in the process is able to untie oneself from the bonds of transmigration.
Guru Nanak had said that when an individual meditates more and more on the name of God, he or she goes more close to the Almighty. Taking the Nam with complete devotion disinclines a man from being subject to his or her Haumai or evil impulses. As a result the heart of individuals becomes purified and he or she is able to detach from all worldly attraction or Maya. Moreover constant meditation gives human mind the grace of God and he is able to walk in the path of righteousness. When an individual walks in the path of Truth he becomes one with the Lord and in the process attains salvation which according to Nanak is the ultimate goal of human life.
Guru Nanak had given much importance to the ascent of man to the ultimate climax. He had said that the goal of life should be directed towards ascent to the ultimate place where dwells the eternal Truth and where it is possible to achieve union with the Lord. Thus he said that all efforts of human beings should be such that they are able to receive the grace of Lord and in the process attain emancipation from the cycles of birth and death.
Nanak had said that ultimate stage of human ascent comprises three essential conditions. The first is absolute union of the individual human soul with the God-the ultimate reality. Secondly it brings a permanent end to the process of transmigration and the human soul can rest in a state of changeless tranquility. Last but not the least Nanak had said that the state of union cannot be expressed; it is a matter of personal experience. Nanak had explained the concept of ultimate experience by saying that it is a blending of the individual atman into the Parmatma. He had said that with the dedicated Nam of the Lord an individual is able to attain the state of union with the Almighty. He had also explained the state of ultimate experience as a state of supreme wonder or visamad. The state of ultimate experience enables man to fulfill the final goal of life.
Thus for Guru Nanak, discipline comprises inner discipline. He had focused that in order to achieve the grace of the Lord it is necessary to cleanse ones heart and walk in the path directed by Truth.