YHWH - these letters appear together over 6500 times in the OT, a name for God whose translation was lost as it was unused to keep from the possibility of taking it in vain. Rendered as LORD in most Bibles, we loose the meaning. YHWH - the self existent omnipotent God.
Jehovah Jireh - the God who provides. I find it interesting that in Genesis 22, when Abraham is asked to sacrifice his son, his only son, the fulfillment of the promise of nations, he knows already that God will provide. His obedience is total, his faith secure, not matter what it is the LORD asks, He will provide.
Jehovah Raah - the Lord our shepherd. The 23 Psalm can teach us a lot about God. He leads us, He doesn't drive us or heard us like cattle. We can know His voice. Jesus used the wonderful language of the shepherd in John 10. The shepherd protects His sheep, fighting off evil. One person in my group had the visual of Jesus with a light saber.
Jehovah Rapha - the Lord our Healer. In Jeremiah 30:17 the Lord promises to heal His people. People who had rejected Him and gone their own way, people who did not listen to His warnings, people who were called rejected by those around them. Jesus healed many while on earth, not just physically. He healed spirits and hearts and minds. No matter what the cause of our pain, the Lord with heal.