How many births did each tirthankar have before attaining tirthankar pad

All Tirthankaras are said to have completed 27 prior births before the final human birth in which they become a Tirthankar (and then attain kevala jnana later). So, 27 previous lives precede the moment of becoming a Tirthankar. Minor details of the narrations may vary between Digambar and Śvetāmbara traditions, but the core idea (27 purva-janmas) is shared.

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