I don't know if you have heard the saying, "once saved, always save". It may sound like a nice saying. But it is a lie straight from Satan. Once you repent of your sins and make Jesus the Lord of your life. That's just the beginning of a gigantic war against Satan.
Satan wants to deceive us. He wants to destroy us. He wants to make us think that once we become Christians life is or will be easy. But it is not. Life is a continual war against Satan, filled with much difficulty.
And every day we need to choose to fight against Satan with all we got.
Every day we need to choose to be on God side.