I recently purchased the book The Power of Now by Eckhart Tolle because I was intrigued by this idea:
Depression is dwelling on the past, anxiety is dwelling on the future, and peace is dwelling on the present.
Maybe you’ve heard something like that before. There is a very similar quote attributed to Lao Tzu, although I’ve heard that it may be questionable who really said it.
But this idea that living in the present moment is the key to peace and happiness has been something I have been pondering for a while.
The premise of Tolle’s book is that depression is experienced because we are dwelling on negative feelings about the past, like regret, guilt, or self-loathing. Anxiety is experienced when we negatively dwell on the future, causing feelings of fear, worry, or dissatisfaction with life in general. True peace and happiness, according to Tolle, comes when we stop living so much in our heads, and take time to be present in the here and now.
There are examples in the Bible that would seem to echo this idea. The Lord’s prayer (Matthew 6:9-13) uses the phrase “give us today our daily bread” (NIV), which could imply that we only need to ask God for things concerning today (we don’t need to ask him for tomorrow’s bread, we just need today’s.) A little later in chapter 6, it says “therefore do not worry about tomorrow, for tomorrow will worry about itself.”

In the book of Exodus, when the Israelites are wandering in the desert, God provides daily food for them – manna and quail (ch. 16). The people are instructed to “go out each day and gather enough for that day.” Anyone who gathered more than a day’s worth found it to be rotting and “full of maggots” by the next morning.
Mindfulness, the practice of being fully present with where we are and what we’re doing, has been gaining popularity in Western culture over the past decade or so, and it also heavily utilizes the present moment, the NOW, to decrease stress and anxiety. Mindfulness meditations typically have you focus on sensations in your body and view your body and thoughts in a non-judgmental way. Headspace, one of my top picks, is a great app to check out for guided mindfulness meditations.
Obviously the idea of there being power in the now is not new or uniquely attributed to one person.