Jainism does not have a concept or phrase "Vasudev ka bal." In Jain literature and practice, Vasudev (Vasudeva), as known in Hindu tradition as Krishna’s father or as Krishna himself, is not a revered figure in the Jain pantheon. Jainism focuses on the 24 Tirthankaras and the Mahavira path, along with its own stotras and mantras that honor those Tirthankaras, not Vasudev.

If you were asking about a Jain prayer, mantra, or stanza that mentions a protector or strength (bal) in a Jain context, please share a bit more detail (e.g., a specific stotra or scripture), and I can explain its correct Jain meaning and tradition.