When we give Dana (alms) and take precepts, we do not use up our old merit. Our Parami (Perfections), accumulated in past lives, enable us to take rebirth as human beings in a Buddhist environment and to find the Triple Gems. As a result we try to practise the Dhamma every day.
The daily meditation with which we persevere is new merit. Chanting, worshipping the Buddha, and giving Dana are considered the new merit which will bear fruit in future.
The Puñña (old merit) created the human form, complete with mindfulness and wisdom. During our lifetime we practise the Dhamma. It means that the result of the old merit brings about our contact with the Triple Gems and the new merit is gained by the continuation of practice.
Our effort to practise day and night can be thought of as the new merit of this life. Both sorrow and joy which are the results of kamma in this life also belong to new merit. After a long period of practice, it will become an inner treasure, called “The Sublime Treasure”, which fills the mind and later turns in to precepts, concentration, the Path and the Phala (Fruitions).
If the mind is not yet full, the merit can be collected to bear fruit for subsequent lives.
If the effort and patience are strong enough and the Perfections accumulated in this life are fulfilled to the highest level, we will be spontaneously Enlightened. If we have not done enough, we can go on collecting them for the future. Suppose a person has completed his Perfection for the period of one Asankheyya (which is incalculable) and 100,000 kalpas (aeons); it means that he has taken rebirth and meditated 1 million times or 2 million hours. When he has completed all of this, he will be enlightened automatically. For people who have not reached the Goal in this life it is as if, perhaps, they have not meditated these 1 million times, perhaps only half that number. They can save this half as the Sublime Treasure for the future. If they continue to meditate, once they have done 1 million meditations, they will immediately become an Arahat.