Have you ever noticed what moves a person to tears? Have you ever thought about what moves you to tears? Does sin and rebellion against God move you to tears? Does the consequences of sin in the lives of other people move you to tears? How about injustice, war, and poverty? Do these move you to tears? They did Jeremiah.
Many of us are prone to mourn because things aren't going our way. But the book of Lamentations is a picture of a man who grieved with God. The things that make God grieve brought tears to Jeremiah.
Jesus was the same way. As he anticipated yet another destruction that was to come on Jerusalem for their sin, he stood overlooking the city and mourned for her: "O Jerusalem, Jerusalem, you who kill the prophets and stone those sent to you, how often I have longed to gather your children together, as a hen gathers her chicks under her wings, but you were not willing. Look, your house is left to you desolate." (Matthew 23:37-38)
Do you see the world through the eyes of God? If you do, you will find yourself more and more like Jeremiah and Jesus, mourning over sin.