There are two ways to deliver the deceased. One is performing meritorious deeds on their behalf and informing them about what's being done, so that they will know to let go and their mind will turn from evil towards good. The second is to teach them the Dharma using one of two approaches. One is to guide them with the Dharma and encourage them to seek rebirth in Amitabha Buddha's Pure Land. The other is to do repentance prostrations, release burning mouths, and recite sutras for them, basically in rituals, to help them open their minds, cease suffering and attain happiness.
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