When we are converted, our old life dies. At baptism our old life is buried. Then God washes away the old sinful life. The past was buried at baptism, and we have a new life in Christ. This tells us that baptism is very important.
Baptism is the beginning of a new life.
The old sinful life is buried and forgotten forever. Yes, The Bible tells us to be baptized. God holds us responsible for what we can do. God will not ask us to do something that is physically impossible. If the thief could have come down from the cross, he would have immediately been baptized.