QUESTION: WHY DO SOME PEOPLE CALL SRI KRISHNA "SUPREME PERSONALITY OF GODHEAD" WHILE NO VEDIC SCRIPTURE DESCRIBES HIM SO?

Sometimes I feel, as Dwapar Yuga i.e. period in which Krishna stayed at earth, was only 5000 years old, we have found many things which proves the existence of him like submerged Dwarka Nagari (in Gujurat), Mathura & Vrindawan (in Uttar Pradesh) etc.

However, we are unable to found much more evidence of other Gods which are millions years old. So it might be a reason, people trust the existence of Krishna is more than other deities, so they used to call that "Krishna is the supreme personality of godhead".

BUT, LORD SHIVA IS THE SUPREME DEITY OF ALL THE GOD HEADS AND THE SAME HAS BEEN WRITTEN IN LING PURAN.

Refer:-

http://basicsofhumanlife.blogspot.in/2014/03/birth-of-universe.html

http://basicsofhumanlife.blogspot.in/2014/03/role-of-lord-shiva-in-creation-of.html

QUESTION: WHAT ARE THE BENEFITS OF WORSHIPING GOD KRISHNA?

Worshiping any God will benefit us, but why Lord Krishna in this KALYUGA.

Actually, our holy books said that, when you worship some god, you will enlightened by that god's characteristics, like you will think like the way that god thinks, in short you are following him and you try to think same ways.

Just for an example, Lord Rama, was a very noble & decent god, he was full with mercy, he was very eager to forgive.

But as we know, Krishna Ji, was in DWAPAR YUG, after it, KALYUG was going to start. He was not like Lord Rama, He was on to the path and strict with the laws, whatever u do, u have to suffer, either good or bad. He shows mercy but with a certain low level. 

"HE WAS VERY FOND OF KARMA & THE SAME HE TOLD IN GITA"

Benefits are like, In this Kalyuga period, we have to tackle all types or person, we have to be good with the good, but have to beware from the bad. I personally feel that, Krishna's message was very much applicable in modern time (Kalyuga). If we worship Krishna Ji regularly with devotion, we will think and behave like him only which will help us.

Gita updesh by Lord Krishna to Arjuna