This is an important question, probably for many people.
Mind phenomena are different from material phenomena. One needs to be careful in applying material phenomena to mind phenomena.
An example is given in the Tipitaka (of course I forget the name of the sutta!). A greedy brahmin one time explained to his sons why giving (dana) is of no use. He asked them to bring a sack of rice and started giving away portions to those who were present. At the end there was nothing left. So, he told his sons: “Do you see? I gave away what was in that sack of rice, and what do I have left? Nothing!”.
One would of course gain NOTHING AT ALL if one’s gives with that mentality. The KAMMIC POWER is generated in the javana citta. And that kammic power is unseen. That is the hard part to understand. It is sort of like for someone from 200 years ago (who has time travelled to the present) to understand how a television works.
- But I think you have experienced for yourself the power of javana citta in your metta meditation, as you mentioned before.
- One may give away many “valuable things” without the “inner feelings/compassion” and may get nothing for it.
- One may give away a little something with strong feelings and compassion, and will get a lot back in the future (especially if one was not thinking about such “returns”).
Another thing to clarify is the difference between “conditions (paccaya)” and “causes (hetu)”.
That kammic power that we talked about above, CANNOT become “causes” for another being. The “root causes” must be there in the person receiving. But pattidana can provide the conditions for cultivating those root causes. In a way, what it does is to make the mind of the person receiving “to a better state” for cultivating those existing causes. Those existing causes could be some “good kamma vipaka” accumulated by that person.
For example, one may have a bunch of “good seeds” to plant, but he/she will not be able to get a good harvest unless those are planted in a field with good soil full of nutrients. So, giving pattidana is like giving fertile soil to that person to plant those seeds.
To put it another way: Beings in the lower realms are in a “bad state of mind” most of the time. Receiving pattaidana can make their minds elevated to a better state for at least a short time. During that time, “samanantara” (suitable conditions) are present for that being to be able to “pull some good vipaka” from the “annantara”, i.e., from the kamma bhava.