Jesus taught that one must be as a child to enter the Kingdom of God. But what did He mean? Let's review:
"13 And they brought young children to him, that he should touch them: and his disciples rebuked those that brought them.
14 But when Jesus saw it, he was much displeased, and said unto them, Suffer the little children to come unto me, and forbid them not: for of such is the kingdom of God.
15 Verily I say unto you, Whosoever shall not receive the kingdom of God as a little child, he shall not enter therein." Mark 10:13-15 KJV
And here we have a parallel passage in Matthew 18:
"At the same time came the disciples unto Jesus, saying, Who is the greatest in the kingdom of heaven?
2 And Jesus called a little child unto him, and set him in the midst of them,
3 And said, Verily I say unto you, Except ye be converted, and become as little children, ye shall not enter into the kingdom of heaven.
4 Whosoever therefore shall humble himself as this little child, the same is greatest in the kingdom of heaven.
5 And whoso shall receive one such little child in my name receiveth me.
6 But whoso shall offend one of these little ones which believe in me, it were better for him that a millstone were hanged about his neck, and that he were drowned in the depth of the sea."
It seems to me that for one, Jesus meant that one must be humble as children often are. But in antiquity children were property. If you needed free labor then you had lots of children. To work the fields, to household duties, to sell and to haggle, children did it all. And once they were 10 or so they were trained in their fathers profession. Children were considered adults as soon as they hit puberty.
Children did as they were told. Or they faced harsh punishment.
They were slaves in a sense but they were also an outcast group, they had no say in society or in the direction of their lives. And that's if they were male, if they were female they had even less "rights" or consideration.
So if one were to be given even a meager gift they would be eternally grateful. If they were given the gift of salvation, of eternal reward none would appreciate it more.
But more than that children, for the most part, are still teachable often because they are so humble.
There are many, like the Pharisees who thought they knew it all. Many feel as though they know all they need to know. But the power of the Holy Spirit, the infinite wisdom and compassion and especially the understanding of God cannot be contained in any one book, person or church. To progress to further light and knowledge one must remain eternally teachable.
To do otherwise is to be as the Pharisees both ancient and modern, who think they know it all. They fail to enter the Kingdom and they cause others to stumble on their paths as well. Thus they prevent or hinder those who are trying to choose the right.
"Do the best you can until you know better. Then, once you know better, do better." -Maya Angelou
For me the idea to be as little children means that we must remain teachable. Many interpret this to mean that we must remain sinless and pure. But to live is to make mistakes. To walk means to misstep on occasion. We cannot remain pure or sinless for long. It is destructive and harmful to think we can live up to this impossible goal.
I think that we cannot change who we have been. We cannot change who we are, but we can change who we become. Day by day we can do a little bit better than the day before and over time the difference will be immense.
If we strengthen and nourish the better angels within us and directly take on the Devils within us and refuse to feed our demons then we will progress in character, righteous and grow into further light and knowledge.
Remain humble, teachable and realize the Kingdom of God isn't just among us but it resides within us. We can only enter it through internal work.
We are all God's children. We always will be. He loves us as much as He loves the rest of His children from Jesus to Judas to our children to our enemies. We might not be able to exercise love that all encompassing but we can learn today to do what we can only do tomorrow.