You never really know what the next moment is going to bring,
so living fully in this moment is the only constantly reappearing option for happiness.
Sylvia Boorstein, Happiness is an inside job

Pay attention to those times when you feel like you are rushing. Rushing does not have to do with speed. You can rush moving slowly, and you can rush moving quickly. We are rushing when we feel we are toppling forward. Our minds run ahead of ourselves; they are out there where we want to get to, instead of being settled back in our bodies. The feeling of rushing is good feedback. Whenever we are not present, right then, in that situation, we should stop and take a few breaths. Settle into the body again. Feel yourself sitting. Feel the step of a walk. Be in your body.
The Buddha made a very powerful statement about this: “Mindfulness of the body leads to nirvana.” Such awareness is not a superficial practice. Mindfulness of the body keeps us present.
Joseph Goldstein, Transforming the mind, Healing the World
No activity can be successfully pursued by an individual who is preoccupied … since the mind when distracted absorbs nothing deeply, but rejects everything which is, so to speak, crammed into it.
Living is the least important activity of the preoccupied man; yet there is nothing which is harder to learn… Learning how to live takes a whole life, and, which may surprise you more, it takes a whole life to learn how to die.
Seneca, On the Shortness of LIfe
If we pay attention, we will realize that every moment around us, there is a world that we did not create that’s been there for 13.8 billion years, and there’s trillions of cells in your body that are doing what they’re supposed to do, and all of nature, everything.
You wake up and you realize, “I’m not doing any of this. I didn’t make my body. I didn’t make my mind think. I don’t make my heart beat. I don’t make my breath breathe, etc, etc, yet I have this notion that I have to make things happen. Yet, all throughout the universe, things are happening everywhere and I’m not doing them, so why exactly am I the one that’s in charge of what’s unfolding in front of me?”
What you realize at some point is that you’re not; that the moment in front of you that’s unfolding is no different than all the zillions of other moments that aren’t in front of you that are unfolding in accordance to the laws of nature, the laws of creation. You start to practice saying, “I want to pay attention to what the universe is creating in front of me just like it’s creating everywhere where I’m not, and let me see how I can participate in that – be part of that – instead of interfering with it with my desires and my fears.”
That’s living from a place of surrender.
Michael Singer, Living From A Place Of Surrender, Sounds True Blog