Sant Bhasha (Sant Bhāṣā) is a language composed of vocabulary common to North Indian languages, which was extensively used by saints and poets to compose religious verses. It can be understood by readers with a background in either Punjabi, Hindi or Urdu. It is also called Gurmukhi Language.
Apart from Punjabi and Hindi dialects, Sant Bhasha contains words from Sanskrit, Prakrit, Apabhramsha, Persian and Arabic. It is most prominently used in the Sikh holy book, the Guru Granth Sahib. The languages used include Lahnda dialect of Punjabi, regional Prakrits, Apabhramsa, Sanskrit, Hindi languages (Brajbhasha, Old Hindi, Awadhi, Bhojpuri etc.), Sindhi, and Persian.
References
Sant Bhasha Wikipedia(Text) CC BY-SA