BDBD is Proverb 14:10

The true core mood of a person’s heart is known only by the owner and God (1 Chronicles 28:9). Whether bitter or joyful, happy or sad, fearful or brave, puzzled or enlightened the heart’s presence is thine heart alone. The heart, “leb” in Hebrew (a transliteration) is used to describe the seat of one’s feelings and emotions and is associated with thought and will. Some people may spend years, or even a lifetime, not understanding the depths of their emotions.

The two opposing heart states focused on in this proverb are bitterness (Hebrew “morra”) and joy (Hebrew “simha”). Biblical examples of bitterness are 1 Samuel 1:10; 1 Kings 8:38; & Mathew 26:75 and examples of joy are 1 Chronicles 29:17-22; Ezra 6:16, 22; Easter 8:16; & Matthew 13:44. Though external circumstances and situations will make a person bitter or joyful, the heart’s reaction to these is controlled by the heart’s owner. My ability to control my heart depends on myself alone.

The crucible for silver and the furnace for gold, but the LORD tests the heart.” Proverbs 17:3) A clear benefit of a personal submissive relationship with God is that he matures and molds the heart so that it fares better in every and any life event. So that one event experienced in the past will bring bitterness, yet experiencing it again later will bring joy.

  During the Last Supper, “Jesus saw that his disciples wanted to ask him about this, so he said to them, ‘Are you asking one another what I meant when I said, ‘In a little while you will see me no more, and then after a little while you will see me’? I tell you the truth, you will weep and mourn while the world rejoices. You will grieve, but your grief will turn to joy. A woman giving birth to a child has pain because her time has come; but when her baby is born she forgets the anguish because of her joy that a child is born into the world. So with you: Now is your time of grief, but I will see you again and you will rejoice, and no one will take away your joy.” (John 16:19-22)