We are the accumulation of everything we have ever received from those around us. Life is a constant cycle of give and take, want and need, borrow and steal. The man who has everything started with nothing, and the woman begging on the sidewalk once had more than than the last remnants of her dignity she uses to beg for the last portion of your food.
With the world working so fast it is hard to realize we are constantly giving up the last piece of something we have. When you're sitting at lunch with your friends, you give up the last bite of your meal without even a bat of an eyelash. right outside the door is a man who is giving up his last cigarette to a woman who was begging for that to get her through the day. The man was on his break for work and could have said that it was his, but instead he knew it was all he had and gave it to her anyways. Sometimes all you have is enough.
When you are playing outside in the backyard with your little sister on a hot summers day and run to the freezer to see that there is only one Popsicle left. It's your favorite flavor, but instead you let her have it because it was all both you had at the moment. In turn your dad comes home from a long day at work and is accidentally snappy with you because he had a long day. Instead of being sad and sulking away to your room, you give him a giant hug just to comfort him for a few moments. It wasn't much, but it was all you could give him at the time. To your dad that was more than he could have asked for because at the end of the day you and your hugs are all he has, and that's always enough.
A lot of times we are embarrassed to give people pieces of ourselves because we think we may never be enough, what we have to offer may not impress them or live up to their standards. What we think is not enough could be the world to the other person, what we have to offer is the most amazing thing to another human. Sometimes saying "This is all I have" sounds like "Here is exactly what you needed" to another.