Bhaja Govindam also known as Moha Mudgara is a popular 8th century Hindu devotional composition in Sanskrit attributed to Adi Shankara. Below given Sloka is taken from Bhaja Govindam. Adi shankaracharya emphatically states the importance of devotion for god as a path to reach spiritual development and to liberation from the cycle of birth and death.
भजगोविन्दं भजगोविन्दं गोविन्दं भजमूढमते |
संप्राप्ते सन्निहिते काले नहि नहि रक्षति डुकृञ्करणे ||
Bhaja Govindam, Bhaja Govindam,
Govindam Bhaja Mooda Mathe,
Samprapthe sannihithe kale,
Nahi nahi rakshathi dookrunj karane
Meaning : Worship Govinda, worship Govinda, worship Govinda, Rules of grammar will not save you at the time of your death.