It has been said, "Christianity is not a religon, but a relationship--with God."
More on this topic....
Isn't Christianity mostly just like all other major belief systems? We're sometimes led to believe that.
However, Christianity is radically different from all other world religions. For starters, it is all about coming into a personal love relationship with God.
And that is not by our efforts trying to reach up to Him, but because God Himself reaching down to us in Christ.
"This is love: not that we loved God, but that he loved us and sent his Son as an atoning sacrifice for our sins" (1 John 4:10).
"We love him, because he first loved us" (1 John 4:19)
"He loved us!" First! Before we ever thought about Him (Romans 5:8). And God sent Jesus to pay the debt of sin we owed.
Still more on this topic....
Tim Keller, in The Reason for God, makes the following points:
First, a personal love relationship with God--where His love is poured out in our hearts by the Spirit-- is not a feature of any other religion. In fact, the idea is either be offensive or ludicruous to those beliefs systems. Some don't believe in a personal god at all--so it would be nonsense. Others believe it's not possible or even presumptious and disrespectful toward God (or gods) to consider.
Second, only Christianity teaches that God reached down to mankind in grace. And, it alone teaches that our best efforts to "reach up" to God (or whatever) are worthless. There is nothing: no path, no meditation, no ritual, no good deeds that we can do to reach God (or whatever primary goal other religions have).
In Christianity it is all by God's grace. We can only receive this gift by faith in Christ. Jesus paid for it; we aren't able to. That's the gospel.
Tim Keller states that we can contrast the gospel to all religions (pp. 174ff). It's that unique!
He observes that religions say, "I obey--therefore I'm accepted by God." But the gospel says, "I am accepted by God through what Christ has done--therefore I obey."
Here's something else you hear often: "But aren't all religions climing up different sides of the same 'mountain' toward God?" Again, religions probably are. But God is not at the top of the mountain. He's infinitely beyond it. The gospel is God reaching down in Christ to us. He bridged the gap!