His sin was striking the rock when God told him to speak to it. Lack of faith is a stumbling block to salvation.
Yet Moses had a speech challenge if I not mistaken.
I think, too, that he sinned by taking the credit for the miracle on himself. He probably was so angry and so worn out that he just didn’t think. But God says he shares his glory with no one. Moses wasn’t capable of making water come out of the rock.
The major sin of Moses, was one we all fight daily, if not minute by minute, the hardest for humans to steer clear of: PRIDE!
I’ve always thought that it was in striking the rock TWICE, rather than just once. A lack of trust of God on the part of Moses.
Moses double clicked.
God: MOSES! CLICK the rock once.
Moses click?
God: Ehem ahh... STRIKE, strike the rock once.
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