While the gift of eternal life is free, the cost to those who accept it is very high. Look at it from another perspective. It is technically free to get pregnant and free to have a baby (if you choose to do it all on your own) but the cost to your life in the caring for and rearing that child are high, VERY high. Some might even say you give up your own life when you decide to have children.
Jesus asked nothing less of us than to follow him and give up our life. It was not a glamorous life we are to follow. He made that clear in Matthew 8:20 where he said “Foxes have holes, and birds of the air have nests, but the Son of Man has nowhere to lay his head.” If you get a chance to talk to anyone who is truly homeless they will tell you that while free, it is a very hard life. Jesus promised us hardship and a world that would hate us as it hated him.
I must always remember this and never think that following Jesus will be or should be easy. It is the narrow harder path, but I know that my reward will be GREAT after this life. Look at John 10:10b. “I came that they may have life and have it abundantly.” The word “abundantly” in this context, in the Greek context, and in the context of Scripture as a whole means that we would have life “exceedingly abundantly” or “more upon more” or in denotative terms “life upon life” which means eternal life. This is what I cling to. This is why my life is given up to Jesus as a bond-slave to him.