Exodus 15:25

And he cried unto the Lord, for counsel and assistance; and the Lord showed him a tree, indicated some wood to him, which when he had cast into the waters, the waters were made sweet, as palatable and wholesome as the best drinking-water. In this way the Lord overlooked the weakness of His children and helped them out. There He (God) made for them a statute and an ordinance, and there He proved them,