Meaning: The way you behave now will affect your future. For instance, if you help others, they will also help you. Please note that "ye" is plural and means "you". As a matter of fact, you may also use "you" instead of "ye".
They have been sent to prison for corruption. As ye sow, so shall ye reap.
He has always helped in the community, and now that his house has had to be pulled down, the community will help him to build a new one. As you sow, so shall you reap.