Salvation is Free
The Bible offers free salvation to anyone who come to Jesus Christ and accept him as his saviour. No other religion offers free salvation to people.Let us look into nature for the basic necessary things needed for life given freely from God. The life on earth depends upon free sunlight. All biological systems are totally dependent on it for growth and development. We can not live on this earth without air and water needed by all biosystem and it is also free.Thus, we find that God gives everything for free which is required for sustaining the life. In the same way, God offers free salvation needed for an eternal life.
There is no work which can take us to heaven as we all are sinners.
Work= Force x Distance Cos θ
As heaven is above, the value of θ is 90.
Now the value of Cos 90 is 0.
So Work = Force x Distance x 0
Work = 0
Physics shows that no work can claim the heaven for us. It is through only grace of God through Jesus Christ.