Tapas, Santosha, Astikyabuddhi, Dana, Ishvarapujana, siddhanta Vakya shravana, Lajja, Mati, Japam, Vratam... these ten form Niyama. These are the very foundations of the Mansion of Moksha; all Yogis must be well established in these; in Yama as well as Niyama. (P.Vah, p. 300)
Niyama means the condition of steady Prerana in the Paramatma or Godhead, at all times and under all conditions. (GA, p. 169)
The second set of disciplines is covered by the term niyama. It consists of five practices: shaucham (purity); tapas (austerity); santosham (contentment) svadhyayam (study of scriptures); Ishvara pranidhanam (offering to the lord). (D3 , p. 85)
Niyama: Niyama means purity, being always full of joy, engaged in Tapas or Japam. That is what is mentioned in Raja yoga; Shaucha, Santosha, Tapas, Svadhyaya. Ishvarapranidhana, these are the Components of Niyama.
But, I would explain it in the following manner. Niyama is the condition of steady Prema in the Paramatma or Godhead, at all times and under all conditions ‘Sa Tva Asmin Parama Prema Rupa’, it is said in the Narada Bhakti Sutra).’It is the highest form of Prema’. It is only when such steadfast Love towards the Absolute is gained, that the Shaucha or Purity, the Santosha or Joy, the Tapas (austerity), the Svadhyaya or Study, the Ishvara pranidhanam (offering to the lord or dedicating all deeds to God or Surrendering to the Lord), mentioned in the Raja yoga will become the possession of man through the source of all ananda and Shanti, the Sat-Cit-ananda Parabrahman Entity.
For these two are not derived from the dry worldly material objects. ‘raso vai sah’ He is Sweetness, ‘Anandam vai Brahma’ Brahma is ananda, says the Upanishads. It is in and through Brahma that the material world is endowed with even the tiniest modicum of joy. Without the basic Brahma, which is the completest and the fullest sweetness and joy, this fleeting evanescent appearance thereon cannot be so sweet and joy giving to the worldly-minded! It would have been, without that basic rasa, terribly bitter. For this little sweetness that material objects give, that Ocean of Nectar is the cause.
The association with the knowers of Brahma, discussion with them of the Nature of the Absolute in a spirit of humility and earnestness, a thirst to realise the Reality, unwavering Prema towards the Lord, these are the characteristics of those established in Niyama.
Such stalwarts will not be affected by derision or praise by wind or sun or rain, by honour or dishonour; they will tread the path of liberation free from all attachment to anything except the one single aim of realising the ananda of Union with the basic Brahma.
He who has realised the stage of Niyama will be ready to sacrifice everything for the acquisition of Jnana. He will run to any distance to listen to discussion of Brahman; he will obey every instruction of the wise; he will attach himself to those who teach him the science of ultra-consciousness or Chinmaya tattva, as if they alone are his most-intimate friends; he will put up with any trouble in fulfilling their wishes. These are the signs of the Niyamastha, or person who has achieved Niyama. (P.Vah, pp. 66-67)
Bhagavan Baba says, ‘I suggest that you follow discipline and lead a simple life wherever you live. You may go to any place, but there also you should always follow niyama, discipline, have shraddha, sincerity, and take to sadhana, spiritual practice. This is the spiritual way of life.
The fourth niyama is svadhyaya or study of the Holy Scriptures. You should read every day one Holy Scripture. This is called parayana, worshipful reading of a religious book every day. This cleanses your mind to some extent. (Satyopanishad)