The Primordial Power is ever at play. She is creating,
preserving, and destroying in play, as it were. This power is called Kali.
Kali is verily Brahman, and Brahman is verily Kali. It is
one and the same Reality.
When we think of It as inactive, that is to say, not engaged
in the act of creation, preservation, and destruction, then we call It Brahman.
But when It engages in these activities, then we call It Kali or Shakti.
The Reality is one and the same; the difference is in name
and form.
Sri Ramakrishna Paramahamsa
Source - The Gospel of Sri Ramakrishna – (page 134 – 5)