"a time to scatter stones and a time to gather them, a time to embrace and a time to refrain," NIV translation
Now, Solomon examines the timing of our physical actions on this earth. There is a time in all of our lives when we are to gather the things (stones) that we need for building our life on this earth. Many spend a long time in this season with their focus on gathering more stones than those around them in order to climb the ladder of success. In other cases, people ignore the gathering of stones and instead focus on their physical pleasure.
"a time to search and a time to give up, a time to keep and a time to throw away," NIV translation
Many people spend their lives chasing the future and some people spend all of their time caught up in the past. Although we can spend time remembering the past and dreaming about the future, we live in today and must keep focused on the task at hand to be productive.
"a time to tear and a time to mend, a time to be silent and a time to speak," NIV translation
In our dealings with others, sometimes we have to tell them some harsh realities of life but we can do this with love to build them up. There is a time for us to talk but we must also listen in order to have a conversation.
"a time to love and a time to hate, a time for war and a time for peace." NIV translation
In this world (under the sun), there have been periods of relative peace and times of great wars. We were told by Jesus that there would be even more times of war as we get closer to His return.
"What does the worker gain from his toil? I have seen the burden God has laid on men. He has made everything beautiful in its time. He has also set eternity in the hearts of men; yet they cannot fathom what God has done from beginning to end." NIV translation
The "burden God has laid on men" speaks of the battle that goes on inside of each of us. This battle is between the flesh/physical (under the sun) and the spiritual (under the Son). God has made the earth a wonderful place to live with all kinds of wonderful things for us to enjoy. Even with all that is around us, we still have a yearning to live forever (eternity) and to know what lies ahead for us. The first part of this battle (determining our place in eternity) is very simple as we must accept Jesus Christ for our salvation. The second phase of the battle which is walking the talk continues until we pass on or until Jesus comes back to get us. This battle is the fight to remain focused on the things of God in a world of distractions. Our simple minds cannot understand how or why God created all of this and the depth of His love for us in sending His Son here for us.