reap what you have sown

源自《圣经.加拉太书》:Be not deceived ;God is not mocked: for whatsoever a man soweth, that shall he also reap.(不要自欺欺人,上帝是不可以欺骗的,因为人种什么,就会收什么.) 

to win or lose as a result of something you did in the past

种瓜得瓜，种豆得豆;善有善报，恶有恶报

Trying to get without first giving is as fruitless as trying to reap without having sown.

没有先付出就想要得到，犹如没有播种就想要收割般徒劳。