All boils down to the fact that according to God, as expressed in His Holy Hymns, salvation for the Mankind is possible is possible only through continuously saying His Name (ਨਾਮੁ ਸਿਮਰਨ). Now the question arises as to where to get His Holy Name from and who is going to administer it to us? Let us see what God tells us through His Holy Hymns about it.
ਸਚੈ ਸਬਦਿ ਸਚੀ ਪਤਿ ਹੋਈ ॥ ਬਿਨੁ ਨਾਵੈ ਮੁਕਤਿ ਨ ਪਾਵੈ ਕੋਈ ॥
ਬਿਨੁ ਸਤਿਗੁਰ ਕੋ ਨਾਉ ਨ ਪਾਏ ਪ੍ਰਭਿ ਐਸੀ ਬਣਤ ਬਣਾਈ ਹੇ ॥੯॥
No one will evr achiev salvation (ਮੁਕਤਿ) without His name. It is only by virtue of the Holy Name (ਸਚੈ ਸਬਦਿ) that one is honoured by God. God has so willed that His Name can only be administered to the man by the Almighty Guru (Guru Nanak) and no body else.
ਆਪੇ ਆਪਿ ਆਪ ਹੀ ਆਪੇ ਸਭੁ ਆਪਨ ਖੇਲੁ ਦਿਖਾਧਾ ॥
ਪਾਇਓ ਨ ਜਾਈ ਕਹੀ ਭਾਂਤਿ ਰੇ ਪ੍ਰਭੁ ਨਾਨਕ ਗੁਰ ਮਿਲਿ ਲਾਧਾ ॥੪॥੬॥
God by Himself is All-in-all, and he Himself is running the entire show of the universe. He cannot be achieved by any means whatsoever except with the grace and guidance of the Guru. Thus the possibility of any other individual except Satguru administering His Name to the mankind, is ruled out.
ਅਨੇਕ ਜੂਨੀ ਭਰਮਿ ਆਵੈ ਵਿਣੁ ਸਤਿਗੁਰ ਮੁਕਤਿ ਨ ਪਾਏ ॥
ਫਿਰਿ ਮੁਕਤਿ ਪਾਏ ਲਾਗਿ ਚਰਣੀ ਸਤਿਗੁਰੂ ਸਬਦੁ ਸੁਣਾਏ ॥
One may take birth for a countless number of times in search of salvation, he will never find it without the help of Almighty Guru. He will get salvation only when he seeks Satguru’s protection and the Satguru initiates him with Holy Name.
ਨਾਮਹੀਨ ਧ੍ਰਿਗੁ ਜੀਵਤੇ ਤਿਨ ਵਡ ਦੂਖ ਸਹੰਮਾ ॥
ਓਇ ਫਿਰਿ ਫਿਰਿ ਜੋਨਿ ਭਵਾਈਅਹਿ ਮੰਦਭਾਗੀ ਮੂੜ ਅਕਰਮਾ ॥੩॥
ਗੁਰਿ ਸਤਿਗੁਰਿ ਨਾਮੁ ਦ੍ਰਿੜਾਇਆ ਜਨ ਨਾਨਕ ਸਫਲੁ ਜਨੰਮਾ ॥੪॥੨॥
Those who are devoid of Holy Name are the cursed ones and they live an aggrieved life. they are unwise and unfortunate and are spun in the never-ending cycle of birth and death. their life becomes blessed and worthwhile only if and when Guru administers the holy Name to them.
6. In fact the real purpose of life is not only to eat, drink, dress best, and indulge in material enjoyments (this we have done enough in our past lives as insects, birds and beasts) but to live just well, in order to be able to say God’s Name all the time. God’s pleasure will thus accrue to us and bring in its wake all the benefits of life along with ultimate salvation through communion with the creator, which is the sole object of our life
7. God has empowered only Satguru (Guru Nanak) to administer His Holy Name to the disciples thus enabling them (disciples) to keep on saying the Holy Name (ਨਾਮੁ) for the rest of their lives. Except Satguru no other person on earth is empowered to perform this ceremony of administering Holy Name.
8. Guru Sahib (i.e. from Guru Nanak to the 10th Guru, Guru Gobind Singh Sahib), personally performed the ceremony of baptising disciples by making them drink Holy Water (Amrit) first, and then initiating them with Gur-Mantar (the name of God) to them, and also urging them to say Holy Hymns (ਗੁਰਬਾਣੀ) in their daily prayers in the set order.