怎么理解这句话 ：your strength is in your will --- not in your arm

怎么理解这句话 ：your strength is in your will --- not in your arm summer in your arm 歌词 I just want die in your arm~ When you hold me in your arm you're not alone i will always in your mind 请问这句话大概中文意思, melt in your mouth ,not in your melts in your mouth,not in your How long is your arm?怎么回答. This sernice is not available in your ()your arm() What is your greatest strength? you will enjoy your stay here.这句话怎么理解,这里的为什么是your呢?