By all means we should totally want to hear fully what Chrsit is saying here, meaning of course all of the words He said at that time.
Right?
(Imagine in contrast, if you did not have a bible available, and I was the preacher, and then I only allowed you to read one isolated verse, then you ought to wonder what else was being said! You ought to wonder why I'd only given a single verse. You ought to wonder if I had some agenda, to hide the other verses....)
Let's look, what is Christ saying about 'little ones'? Now, let's hear the full quote.
1 At that time the disciples came to Jesus and asked, “Who, then, is the greatest in the kingdom of heaven?”
2 He called a little child to him, and placed the child among them.
3 And he said: “Truly I tell you, unless you change and become like little children, you will never enter the kingdom of heaven.
4 Therefore, whoever takes the lowly position of this child is the greatest in the kingdom of heaven.
5 And whoever welcomes one such child in my name welcomes me."
6 “If anyone causes one of these little ones—those who believe in me—to stumble, it would be better for them to have a large millstone hung around their neck and to be drowned in the depths of the sea.
7 Woe to the world because of the things that cause people to stumble! Such things must come, but woe to the person through whom they come! ..."
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Matthew 18 NIV
Is this all? Well, a person wanting to know all Christ is saying will of course keep reading.... and then they will find out there is more....
The rest:
...
(next chapter, quite soon)
10“See that you do not despise one of these little ones. For I tell you that their angels in heaven always see the face of my Father in heaven.
[whoa!]
...
13 Then people brought little children to Jesus for him to place his hands on them and pray for them. But the disciples rebuked them.
14 Jesus said, “Let the little children come to me, and do not hinder them, for the kingdom of heaven belongs to such as these.”
15 When he had placed his hands on them, he went on from there."
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Ok, this should be enough to tell us it's not merely those new in faith, but another thing or 4 is happening. The Kingdom of Heaven belongs to such as ...children specifically, even those not even yet understanding much, or having been converted.... It's plainly there. So, it's time to think more on it, if one though it was only about new believers alone. Of course one key lesson we should get from the above passages is that humility is very central to being His. One can confirm this accidentally just by generally reading in the Bible:
Psalm 138:6; Proverbs 3:34; Proverbs 29:23; Matthew 23:12; Luke 1:52; James 4:6; 1 Peter 5:5
Same lesson, in many different ways.
Ok, that's 1 thing.
What else? See? It's a process of listening.