You called in trouble, and I delivered you; I answered you in the secret place of thunder: I tested you at the waters of Meribah. Selah.
Read Chapter 81
George Leo Haydock
In the secret place of tempest. Hebrew, of thunder. When thou sough test to hide thyself from the tempest: or, when I came down to Mount Sinai, hidden from the eyes in a storm of thunder; (Challoner; Exodus xix. 16.) or when I afflicted Egypt, (Exodus ix. 23.) and Pharao's army, Psalm lxxvi. 19.
Contradiction, at Mara, or rather at Cades, where Moses betrayed some distrust, Exodus xxiv. 25., and Numbers xx. 12. (Calmet)
After so many benefits, they still contradicted God, and would not serve him. (Worthington)