Sin is the disobeying of God's commandment and doing contrary to what he commands us to do.
The first sin can be traced back to the time of Adam and eve. They ate the fruit which God commanded them not to eat and the result was disastrous. Initially Adam and eve were suppose to live forever on a beautiful paradise earth but they chose to disobey God. It was on that day that God curse them and banished them out of the garden of Eden.
We are the offspring of Adam and eve so therefore we inherited imperfection from them. Adam and eve suffered greatly on the earth and eventually died.
The story of Adam and eve is a vivid and clear example of the penalty of sin,no wonder ROMANS 5:16 says that "sin came into the world through one man and death through sin and death spread to all men because they had sin". The penalty of sin is death.
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Today in this world people suffer and die everyday.Most people are in the hospital and various challenges are everywhere. Humans now grow old and faced the severe trials of old age and eventually die. That is the penalty of sin.
The question now is :IS THERE ANY HOPE FOR MANKIND?
The answer to that question is an emphatic Yes. The true God and our loving father has provided a way for us. The true God sent his only begotten son to this earth to die for me and you in other for us to be saved(John 3:16). source
God love us so much and he don't want us to suffer that was why he sent his son to die in our behalf. The death of Jesus wash us free and made us to be acceptable once again be God.
Now once again humans will have the hope of the resurrection to life those who are dead and living in the glory of the God all thanks to JEHOVAH for coming to our rescue by giving his son as a ransom sacrifice to die for our sin. This gift is an underserve gift.
Another question now is:IS IT EVERYBODY THAT WILL BENEFIT FROM CHRIST RANSOME SACRIFICE?
The answer is NO. Recall that at ROMANS 5:16 the Bible does not say that all will have external life. It specifically made mention that "whosoever believe in Jesus and exercise faith in him will not be destroyed but have evalasting life" what does the verse implies? It means that Jesus Christ has died for all of us but in other to have everlasting life we need to EXERCISE FAITH in him that is obeying what his father had told us to do which is recorded in the Bible.
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Jesus had died for all of us, now the ball is in our side to play well. One way we can exercise faith in Jesus just as stated above is by applying all the Bible principles in our life, read the Bible regularly and think of ways you can help others, don't forget to pray for your enemies.If we do all these we are exercising faith in God and in his son Jesus Christ.
The penalty of sin is death but we are very grateful that God has provided a ransome sacrifice for us to have everlasting life only if we abide to his laws.