It encourages you to accept life on life’s terms, even when something unfavorable is happening that might be outside of your control. So you’re not resisting what you cannot, or choose not to accept. It’s about saying yes to life, just as it is.
The universal truth is that pain in life is inevitable, but our suffering is optional. We don’t have to agree with whatever has gone down, like it, or approve of it, but we can accept that whatever it is, it’s real and it’s here. Therein lies our power. Because make no mistake, within a feeling of powerlessness, allowing the truth to be is how we regain our footing and move back into alignment.
Accepting reality is difficult when life is painful. No one wants to experience pain, disappointment, sadness, or loss. But those experiences are a part of life. When you attempt to avoid or resist those emotions, you add suffering to your pain. You may build the emotion bigger with your thoughts or create more misery by attempting to avoid the painful emotions. You can stop suffering by practicing acceptance. Radical acceptance does not mean that you embrace the person who hurt you as if nothing happened. You go forward with knowledge that you didn't have before. You stand up for yourself with respect. The anger and resentment serve as messages to be more careful in the future, to stand up for yourself in effective ways, to strengthen your support system, and to use whatever knowledge you gained to be more effective in living your life. Holding on to the anger or resentment handcuffs you to the past and keeps you reliving a painful event. You continue to suffer, though the event is long since passed.
The same information is true if you are angry with yourself. Forgive yourself and move on with what you have learned. Punishing yourself does not help you live more effectively.
The term radical acceptance, I believe was first coined by the American Vispassana Tradition of Buddhism. Though the concept in some form has a long history in all of Buddhism. It has been adopted by Marsha Linehan, who developed Dialectical Behavior Therapy, or DBT
Life gives us lots of opportunities to practice acceptance. If you have a problem that you can solve, then that is the first option. If you can’t solve it, but can change your perception of it, then do that. If you can’t solve it or change your perception of an issue, then practice radical acceptance.Begin by focusing on your breath. Just notice thoughts you might have, such as the situation isn’t fair, or you can’t stand what happened. Let those thoughts pass. Give yourself an accepting statement, such as “It is what it is.” Practice it over and over again. Acceptance often requires many repetitions.
You can read various books related to radical acceptance. They are available online on amazon.