In Genesis 12, God commanded Abraham to leave his homeland and go forth into an unknown country.  Abraham obeyed, but along the way, Abraham allowed fear to influence him and lied to Pharaoh about who his wife was.  He was worried that he would be killed if Pharaoh realized Sarah was his wife.  Abraham found his own solution in response to his fear (which might have been a valid fear; who knows) by lying and saying Sarah was his sister.

​After the obedience of stepping out in faith, God will test your resolve--many times.  He does this to give us opportunities to anchor ourselves even more firmly in Him.