Salt of the Earth

In Matthew 5:13 it is written: (http://www.biblegateway.com/passage/?search=Matthew%205:13&version=NIV)

¹³ “You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot.

We have to pray constantly to God ask him to help us not to lose our saltiness. We need the Holy spirit living in us, so when the others see God in us, in our actions and attitudes, then they will recognize that without God there is no light to guide us out of the darkness. That is the reason why we have to ask God to keep us straight on His path.