The Lotus sutra describes Boddhisattva Fukyo joining his hands in reverent worship as he prayed to the inherent Buddha nature of everyone he encountered. The Lotus Sutra also states: "In facing the Buddha, we must join our hand in prayer;" "it is imperative to join our hands in prayer of wholehearted determination;" "we must show our reverence through our hands joined in prayer to hear about the path with which we are endowed;" and "we must extend greetings by respectfully joining our hands in prayer." This practise is frequently mentioned in the Lotus Sutra.
A passage from Nichiren Daishonin's "Oral Teachings" (Ongi Kuden) states, "Joining our hands in prayer is an alternative expression for the Lotus Sutra." (Shinpen Gosho, p.1734)
Principles such as "Body and Mind", "the Mystic Law", and "Buddhahood and the nine worlds" are all represented in the way we jopin our hands:
The ten worlds are entirely enclosed in the two characters for joining our hands in prayer. All worldly phenomena are contained in the hands joined in prayer.(Ibid.)
The Daishonin also says in the Gosho, "Observations of the Shingon", "The symbolism of joining the hands in prayer is that of the true entity of all phenomena." (Shinpen Gosho, p.612)
Another passage states:
The two characters for joining the hands in prayer are contained in all phenomena. The entities of hell and hunger, respectively, and all the laws of the three-thousand worlds in their present condition join their hands in prayer and face the Buddha. (Shinpen Gosho, p.1734)
This excerpt teaches us that when we, the common mortals of the nine worlds, join our hands in prayer with sincere determination in faith and face the Gohonzon, we become entities who manifest the principles of the "mutual possession of the ten worlds" (jikai goku), the "actual three-thousand realms contained in a single life moment" (ichinen sanzen), and the "attainment of Buddhahood in our present form" (sokushin jobutsu).
Joining our hands in prayer is immediately synonymous with understanding our lives. (Ibid.)
When we pray and devote ourselves to the Gohonzon, we manifest the principle: "Buddhahood is inherent within the nine worlds". Our existences, as we join our hands in prayer, facing the Buddha and chanting Daimoku, are the very manifestation of enlightenment.
Nichiren Shoshu explains the meaning of joining our hands in prayer in the following way: our wholehearted determination is represented by the eight petals of the lotus flower. this is also called the "lotus of the heart" or the "white lotus", and it represents our Buddha nature when we join our hands in prayer. The eight petals are reprented by our eight fingers, and the two thumbs symbolize father and mother or the principles of reality and wisdom and "practicing for spiritual stability and wisdom". It is also said that the ten digits portray the concept of three thousand realms inherent in the ten worlds, and by joining the fingers and palms, we achieve the mutual possession of the ten worlds.
Bringing the joined hands to the chest represents the white lotus of one's heart (determination). Fusing the two entities of body and mind and chanting Daimoku actualizes the principles of "the three categories of action are in themselves the three properties", and "the actual three thousand realms in a single life-moment", and "the Buddha of the entity of the Law".