Keep your fingers crossed When you make a wish, you might cross your fingers (middle and index fingers) as this traditionally brings good luck. If someone tells you they have applied for something and you want to wish them well, you can say: Good luck. I'll keep my fingers crossed for you. You might send a short message to someone expecting news about something important simply saying: Fingers crossed. Many cultures seem to regard cross shapes of various types as lucky. The gesture is probably older than Christianity. Naturally, the importance of the cross to Christianity will have greatly strengthened the positive feeling connected to this idea. The other use of crossed fingers, though, seems positively unreligious. Some people believe that you can tell lies or break your word if your fingers are crossed when you say something or make a promise. A very convenient idea but also a dishonest one! When dealing with young English boys who have heard this it is probably best to make them put their hands open on the table as they speak or make you a promise. A feather in one's cap If you do something well, it is a feather in your cap. Perhaps you win a race, get a medal in the swimming gala, pass a piano exam or do well on an assessment test. For each of these you deserve a feather to put in your cap as a sign of achievement. You may think of Native Americans who were especially fond of feathers and awarded them to young men as a sign of manhood and brave deeds. Leaders would gain many eagle feathers and wear magnificent headdresses to show their status and acts of strength. However, many societies have followed the same custom and used feathers as decoration so there is no need to look so far for the origins of this idiom. Knights and soldiers throughout the ages have also worn feathers as a sign of distinction. So when you do well, you get a feather in your cap. Another feather idiom is to 'feather your nest', obviously arising from birds using some of their breast feathers to make their nests warmer and softer. This idiom however is negative and means looking after your own interests.