This Shabad is by Bhai Gurdaas Ji in Vaars Bhai Gurdaas on Pannaa 1:
sunee pukaar dhaathaar prabh gur naanak jag maahi(n) pat(h)aayaa||
God listened to the cry of humanity & sent Guru Nanak to this world.
charan dhhoe rehiraas kar charanaamrith skhiaa(n) peelaayaa||
Washing His feet, praising God, His Disciples drank the ambrosia of His feet.
paarabreham pooran breham kalijug a(n)dhar eik dhikhaayaa||
He preached God with or without attributes are the same in this darkage.
chaarai pair dhhara(n)m dhae chaar varan eik varan karaayaa||
Dharma now stood on its four feet & all four castes were united as one humanity.
raanaa ra(n)k baraabaree pairee(n) pavanaa jag varathaayaa||
Equating poor with princes, via the touching of feet he spread humility.
oulattaa khael pira(n)m dhaa pairaa(n) oupar sees nivaayaa||
Inverse is the Beloved's game; he got egotist high heads to bow to feet.
kalijug baabae thaariaa saathanaam parrh ma(n)thr sunaayaa||
Baba Nanak rescued this dark age reciting SatNam mantra for all.
kal thaaran gur naanak aayaa ||aa||
Guru Nanak came to redeem this Dark Age.