Thus says the Lord: “Let not the wise man boast in his wisdom, let not the mighty man boast in his might, let not the rich man boast in his riches, but let him who boasts boast in this, that he understands and knows me, that I am the Lord who practices steadfast love, justice, and righteousness in the earth. For in these things I delight, declares the Lord.” (Jeremiah 9:23)
Politicians tell us to look out for devils among strangers. Prophets tell us to look out for angels: "Do not neglect to show hospitality to strangers, for by this some have entertained angels without knowing it." (Hebrews 13:2)
False expectations can often hold us back. The story of Naaman (2 Kings 5) tells of a man who had many false expectations about how God works, and nearly missed out on healing because of it. Fortunately he wised up. How many of us come to the bible with false expectations though?