Bhikkhus, if a bhikhu gains concentration, gains one-pointedness of mind based upon desire, this is called concentration due to desire. He generates desire for the nonarising of unarisen evil unwholesome states; he makes an effort, arouses energy, applies his mind, and strives. He generates desire for the abandoning of arisen evil unwholesome states ... for the arising of unarisen wholesome states ... for the maintenance of arisen wholesome states ...; he makes an effort, arouses energy, applies his mind and strives. These are called volitional formations of striving. Thus this desire and this concentration due to desire and these volitional formations of striving: this is called the basis for spiritual power that possesses concentration due to desire and volitional formations of striving.