To reach the status of a Tirthankar it is not enough to do certain practices during certain birth.  It is the result of a progressive process of unveiling the potential energy through endeavors in right direction during a series of incarnations.  At what point this pursuit started and how it progressed, is detailed in the scriptures.  It seems that the chief disciples or gods must have expressed their curiosity about the journey towards ultimate purity and the Tirthankars must have provided the details.  That is why details of earlier births of all Tirthankars are available.

The counting of these births starts from the birth in which the soul gets the first glimpse of righteousness.  This is considered to be the most important turning point for a soul because once the right direction is attained, liberation is certain.

The loftiest of the pious category of Karmas is said to be the Tirthankar-nam-karma.  It is important to know when and how it is acquired because this is the basis over which the status of Tirthankar is founded.  This Karma is acquired one birth earlier.  It is the physical or normal human body that acquires this Karma.  The aural alternate body (Vaikriya Sharir) does not have the capacity to acquire this Karma.  The future Tirthankar descends from the dimension of gods or ascends from the dimension of hell.  In both these dimensions the souls have aural bodies.  As the aural body does not have the capacity for long-term spiritual practices, this Karma is not acquired during this immediately preceding birth.  That is the reason that all the Tirthankars do their final spiritual practices of acquiring this Karma during their last but second birth as human beings.  During that birth they acquire a high degree of purity of perception.  They become Kshyak Samyaktvi (the level of purity where the past Karmas are destroyed not suppressed).  

The acharyas say that the goal of spiritual pursuit should not be the status of a Tirthankar.  Though its status is very high the Tirthankar-nam type of Karma is still a Karma and as such a tie.  On the path of purity an effort to earn pious Karma is not advisable.  The spiritualists never indulge in any activity that leads to bondage, irrespective of its being pious.  

All activities by spiritualists are directed toward shedding of the Karmas.  As a result of certain activities or practices certain Karmas are wiped and as a consequence this specific bondage is achieved without striving for it.  These practices are numbered twenty.  These are also known as the twenty practices leading to the Tirthankar status and are believed to be the fundamental guiding factors for attaining the status of Tirthankar.  These are:

1.       Worship of the Arihant (Tirthankar).

2.       Worship of the Siddha (liberated soul).

3.       Faith in the discourses.

4.       Worship of the teacher.

5.       Worship of the senior ascetic.

6.       Worship of the scholar.

7.       Worship of these who indulge in penance.

8.       Continued application of knowledge for maximum possible time.

9.       Purity of perception.

10.   To praise the virtues of others and be happy at the progress of others.

11.   To practice the six essentials including Pratikraman (self-analysis) in the prescribed way and at the prescribed time.

12.   Observe all the vows and codes of conducts with ever increasing indulgence.

13.   Detachment-always practice apathy for attachment, fondness, conceit, and greed.  Develop the attitude of being detached.

14.   To activate the potential or to practice penance with all intensity.

15.   To give due importance and respect to the four pronged religious organizations.

16.   To look after and take care of the detached.

17.   To enhance knowledge regularly.

18.   To have faith on the sermons of the detached.

19.   To give charity to the deserving.

20.   Devotion for Tirthankar's sermons and the disciple of the order.

In the eighth chapter of the Jnatasutra and in Avashyak Niryukti these twenty practices are mentioned.  Intense practice of even one or two of these practices may lead to the earning of Tirthankar-nam-karma.  In the Mahapurana and the Tattvarth Sutra there is a mention of sixteen practices of feelings or attitudes.  These encompass all the above twenty practices.  Importance has been given to spiritual practices in both these sets of practices.