It's true that God offers salvation to us as a free gift -- and the reason is because Jesus Christ has already paid the price for it by giving His life for us. The Bible says, "For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord" (Romans 6:23).
But like any other gift, God's gift of salvation must be received. Think of it this way. Suppose a friend of yours wanted to give you a gift. What would he do? First, he'd go out and purchase the gift, selecting it and then paying the price for it. Then he'd offer it to you -- free and fully paid for. But what must you do? The answer is simple: You must receive it in order to make it your own. Until you did, the gift wouldn't be yours.
The same is true of God's salvation. On the cross, Jesus Christ -- who was without sin -- took upon Himself your sins and mine, and He endured the divine judgment that we deserve for our sins. He paid the price for our salvation, and now He offers it to us as a gift -- free and fully paid for. But we must receive it and make it our own, by opening our hearts and lives to Jesus Christ.
Don't turn your back on Christ. After all, He didn't turn His back on you -- and now He wants to receive you and welcome you into His family forever. Commit your life to Him today.