The 3 Stages of Mental Perfection:

The
10 Mental Perfections (paramis =
paramitas) are:
1:
Generosity (Dāna)
2:
Morality (Sīla)
3:
Withdrawal (Nekkhamma)
4:
Understanding (Pañña)
5:
Enthusiastic Energy (Viriya)
6:
Patient Forbearance (Khanti)
7:
Honest Truthfulness (Sacca)
8:
Resolute Determination (Adhitthāna)
9:
Kind Friendliness (Mettā)
10:
Imperturbable Equanimity (Upekkhā)

The
Buddha said:
"These few supreme mental qualities, will culminate in complete
enlightenment.
There is nothing elsewhere beyond them..
Be thorough, firm,
and systematic so to complete them all..."
These 10 mental perfections are developed
to three levels:
I: Those who awaken
as disciples = Savaka-Bodhis give all possessions away
including wife and kids to perfect generosity.
(Similarly with the 9 other perfections...)
II: Those who awaken as
Solitary Buddhas
=
Pacceka-Buddhas give an
organ, limb, or eye away to perfect generosity.
(Similarly with the 9 other perfections...)
III: Those who awaken as Perfect
Buddhas =
Sammāsam-Buddhas
give
even their own life away to perfect generosity.
(Similarly with the 9 other perfections...)
The basic perfection of generosity is the relinquishing of one's children,
wives, and belongings, such as all wealth. The intermediate perfection of
giving is the relinquishing of one's own limbs. The ultimate perfection of
giving is the relinquishing of one's own life. The 3 stages in the perfection
of morality should be understood as the non-transgression of morality on
account of these three: children and wife, limbs, and life. The three stages in
the perfection of withdrawal is the withdrawal of those three bases after
cutting off attachment to them. The 3 perfections of understanding is the
discrimination between what is advantageous or detrimental to beings after
rooting out craving for one's belongings, limbs, and life. The three stages in
the perfection of energy is striving for the relinquishing of these 3 things.
The three stages in the perfection of patience is tolerance to obstacles
to one's belongings, limbs, and life. The 3 stages of perfection of
honesty
is the non-abandoning of honesty due to one's belongings, limbs, and life.
The 3 stages of perfection of determination, as
unshakeable determination
despite the destruction of one's belongings, limbs,
and life, bearing in mind
that perfections ultimately succeed through an unflinching
determination..
The three stages in the perfection of friendliness is the maintaining of
friendliness towards any one, who destroys one's belongings,
limbs, and life!
The 3 stages in the perfection of equanimity is maintaining an attitude of
imperturbable impartial neutrality towards all beings and phenomena, whether
they are helpful or harmful in regard to ones belongings, limbs, and
life.
In this way should this analysis of the mental perfections be understood...

Source:
Commentary on the
Basket of
Behaviour. (Cariyāpiṭaka)
More on the 10 Mental Perfections:
https://What-Buddha-Said.net/library/DPPN/wtb/n_r/paramii.htm
https://What-Buddha-Said.net/drops/IV/The_Ten_Perfections.htm
https://What-Buddha-Said.net/drops/V/The_10_Perfections_Explained.htm