Leaning on God in Our Bitterness

If you witnessed God parting the Red Sea and were a part of all the rejoicing and worship that happened immediately after, how long would it take for you to become desensitized to that experience? How long would it take for you to fall back into complacency, doubt, or an overall questioning of God’s timing, wisdom, plan, etc? A few weeks? A month? A year? Do you know how long it took Israel to go from triumphant praise at the awe-striking power and provision of God to grumbling and complaining over external hardship?