Then the Lord appointed a set time, saying, "Tomorrow the Lord will do this thing in the land." (Exodus 9:5)
God's ways are not our ways, or His thoughts our thoughts, nor His timing our timing. We for the most part desire instant gratification; God knows that those things that come through patients are much more gratifying. We do not like to wait; Jesus said, "By your patience possess your souls." God could have brought the pestilence immediately, but He chose to do so at a set time. I do not know why, I can only speculate; but one thing I do know, God is sovereign. He does nothing without a divine purpose. When I realize that He will not change His thinking, or His timing to mine, then I must by all means change my ways to His. The first step in doing so is to trust Him. The second step, even though at times it must stand alone, is obedience. Because when God says wait, there is no other option.