Various

 "Since past and future have never been without the present, to know the Eternal Now is to know the Truth" - Ramana Maharshi

"The future is a concept—it doesn't exist. There is no future. There is no past. There is only the eternal now." — Alan Watts

"The eternal present is the space within which your whole life unfolds, the one factor that remains constant." — Eckhart Tolle