I read this short story back in the late 80's. It was part of sci-fi anthology, translated into Russian.
The story follows an immortal being that can travel throughout the universe as pure energy (or thought) with other such beings. He gets bored of this existence, leaves the flock, and stumbles upon the modern-time Earth. Being curious about inhabitants, he takes human form by growing himself a body of a man.
The rest of the details are very hazy. While human, he meets a woman and falls in love with her. After a while, he leaves the body but gives it its own "new" identity.