My Identity is self-evident, as are my rights, endowed upon me by my creator, they need no witness, no certification, no record or agreement.

If I put my mark on something, I can attest to it, as can the witness to the event. That mark might be special for just that event.

Now, if we are to go strictly by the law, I should dip the great toe of my right foot into the blood of the sacrificial animal and seal the covenant record. That is where the "Thumb print in red ink" comes from.

I am is self-evident, Word bonded and blood atoned.