In other words, the object of the veneration is literally enlightenment itself in the physical form and the act of making offerings becomes an act of accumulating merits.
Merit is accrued in reliance on the power of the object, which is a fully awakened Buddha.
Therefore, we take refuge, make offerings and supplications to the Buddha via the three doors so that we create the direct causes to acquire the same qualities as the Buddha.
The Buddha’s body is represented by a Buddha statue, thangka or tsa-tsa (small votive Buddha figure in relief), the Buddha’s speech is represented by a Dharma text like the Lamrim, the Perfection of Wisdom Sutra or any other Dharma text and finally, the Mind is represented by a Stupa, a votive mound-like structure.
Besides being a representative of the Buddha body, the Buddha images on the shrine are also excellent visual cues for those who have trouble visualizing and meditating on a complicated Tantric Buddha like the 12-armed Heruka and so forth.
On top of that, there’s an order to which the representations of the body, speech and mind are traditionally placed on a shrine.
The Buddha statue or the Buddha’s body is the central figure on the shrine while the Dharma text or the Buddha’s speech is placed on the left side and the Stupa representing the Buddha’s mind rests on the right side of the shrine.