ThinkigOne ji,
The way I see it that the message is the same in the first verse of the first pauri and the first verse of the 6th. Hence according to my understanding SOCH in the first one is same as TIRATH ISHNAAN.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/jap-ji-sahib/400-japji-sahib-pauri-6-a.htmlReference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=400
If I were you I would read different interpretations of the same from different scholars so that you can draw your own conclusion.
Peace & Love
Tejwant