What is the gist of Heidegger's idea about 'being'?

Question

I was reading Heidegger's Basic Concepts and came across the following quote:

"the casting-toward of being and the casting away of being are equally essential" (P. 75)

I do understand that only when we remain in relation to a certain thing, we can experience the absence of that thing. I was wondering however why he thinks this relationship is equally essential. And besides, I don't quite understand what he means by "the casting-toward of being and the casting away of being" Furthermore, he also mentions:

"After all, what can disturb us about the fact that being casts itself toward us and we immediately cast it away. even though we lay claim to it?"

What exactly does he mean by this question?

Answer 1

Here is a link to the full page for anyone trying to make sense of it.

The piece seems to be arguing the necessity within each of our human experiences to both understand ourselves as conscious entities with physical and emotional needs; as well as explain the usefulness of shedding ones self worth to take on new subjective importance with reference to groups we associate with or tag ourselves to no mater the magnitude.

Once we grip onto self consciousness we spend the next some fifteen to twenty years inventing and re-inventing ourselves because that's how important that one piece of our identity is to our conscious being. Then we inevitably begin to see how we section ourselves out based on loose categorizing and over generalizing how we might "fit in". This is a case of noticing that a person seems to be more satisfied when surrounded by people who have similarities to us of any kind as well as the pack mentality of safety in numbers but it's even more than that. Socially we like to partake in a hive mind or a collective. Losing oneself to a purpose goal or group only to be a part of "something greater than ourselves" this is the importance of letting go of your own being taking on the collective identity both gives you clearer goals as well as security that no matter what happens this group has this purpose and if you ever want to for example feel excitement again you can always go to a concert. If you want to fill the hole of an outgoing and fun person you can always walk into a club! These places provide a label or facade that we get to take part in whenever we want with little to no commitment on our part. Religion, social groupings, or team situations let you shed your problems and ground yourself in a desire thats shared amongst the collective. This also opens us to closer relationships with others and empathy is another characteristic that comes from letting go of one's self. When you put your own issues aside and begin to look to understanding someone else's point of view you gain an understanding of the world and many truths we don't normally consider. This is a crucial stage in development for children and it comes from social interactions something that happens much more organically in group settings.

Answer 2

After reading the section from which those quotes come (thanks @CooLeeo for the link in your answer!), I think I have a better idea of what Heidegger means. First, the "casting-toward of being" means something like "just existing without thinking". I am reminded of the humorous poster of an ape or orangutan with the caption "Sometimes I sits and thinks. And sometimes I just sits." The key to the "casting-away of being" is Heidegger's opening sentences of the section about how as soon as you start thinking or talking about what "being is", you are necessarily "casting away" (separating yourself) from being itself. I.e. you're no longer "just sitting" without thinking. As to both "being ... essential", the context suggests that by "essential" Heidegger merely means "part of the essence of our (human) universe", not "required" or "necessary" as the term means in English. (I suspect a translation issue.) Or in other words, "that's just the way it is".

Likewise, by the second rhetorical question, Heidegger seems to just be tacking on the additional "why worry about it?", or even "regular people aren't distressed by the situation, why should philosophers be?", or "this is our (humans') natural state, so deal" :-).