'Unawares' in the Bible

that the manslayer might flee thither, who should kill his neighbour unawares, and hated him not previously, that fleeing to one of these cities, he might live:

Let destruction come upon him unawares, and let his net which he hath hidden catch himself: for destruction let him fall therein.

But take heed to yourselves lest possibly your hearts be laden with surfeiting and drinking and cares of life, and that day come upon you suddenly unawares;

Be not forgetful of hospitality; for by it some have unawares entertained angels.