Verses about 'demonstrating gods power'
Luke 4:36
And they were all amazed, and spake among themselves, saying, What a word is this! For with authority and power he commandeth the unclean spirits.
Psalms 66:7
He ruleth by his power for ever; his eyes behold the nations; let not the rebellious exalt themselves.
Psalms 77:14
Thou art the God that doest wonders: thou hast declared thy strength among the people.
Job 37:5
God thundereth marvellously with his voice; great things doeth he, which we cannot comprehend.