SB 7.15.64

yad brahmaṇi pare sākṣāt
 sarva-karma-samarpaṇam
mano-vāk-tanubhiḥ pārtha
 kriyādvaitaṁ tad ucyate
Synonyms: 
yat — that which; brahmaṇi — in the Supreme Brahman; pare — transcendental; sākṣāt — directly; sarva — of all; karma — activities; samarpaṇam — dedication; manaḥ — by the mind; vāk — the words; tanubhiḥ — and the body; pārtha — O Mahārāja Yudhiṣṭhira; kriyā-advaitam — oneness in activities; tat ucyate — it is called.
Translation: 
My dear Yudhiṣṭhira [Pārtha], when all the activities one performs with his mind, words and body are dedicated directly to the service of the Supreme Personality of Godhead, one reaches oneness of activities, called kriyādvaita.
Purport: 

The Kṛṣṇa consciousness movement is teaching people how to come to the stage of dedicating everything to the service of the Supreme Personality of Godhead. Kṛṣṇa says in Bhagavad-gītā (9.27):

yat karoṣi yad aśnāsi
 yaj juhoṣi dadāsi yat
yat tapasyasi kaunteya
 tat kuruṣva mad-arpaṇam

“O son of Kuntī, all that you do, all that you eat, all that you offer and give away, as well as all austerities that you may perform, should be done as an offering unto Me.” If whatever we do, whatever we eat, whatever we think and whatever we plan is for the advancement of the Kṛṣṇa consciousness movement, this is oneness. There is no difference between chanting for Kṛṣṇa consciousness and working for Kṛṣṇa consciousness. On the transcendental platform, they are one. But we must be guided by the spiritual master about this oneness; we should not manufacture our own oneness.