We can perform three tests to prove that Namo Amitābhaya is effective. This can also be used to verify how deep our own practice has already become.
Test I: Above, we learned how to produce mantra-water. For this test we use two bottles of the same still mineral or tap water. One of the two bottles we place out of reach. The other one we transform into mantra-water. Then we taste the water from both bottles. The taste is very different. The mantra-water tastes softer and more alive. To verify it, we can let other people, who do not know anything about our experiment, try to taste the difference.
Test II: We pour milk into two glasses, cover them with a sheet of paper and let them stand for one week out of the refrigerator. During this week, we treat one of the two glasses of milk with the mantra Namo Amitābhaya for at least 20 minutes every day (following the same procedure, which is used for producing healing water) or we just let it stand in the same room where we do our daily ceremony. The other glass we do not treat but keep it under the same external conditions (room temperature, etc.). After a week we lift the paper sheets from the glasses and notice the difference: the Amitābha milk can still be drunk, it is still fresh, whereas the other milk is spoiled or bad (alternatively, you can perform the same test with boiled rice).
Test III: Before you chant the mantra you bend over with legs stretched and allow your arms to hang loosely. Your notice how far you reach with our hands effortlessly. After you have chanted the mantra you repeat the same movement and we will notice that your hands reach further down, that you have become more flexible.