9 Jesus also told this parable to some who trusted in themselves that they were righteous,  and treated others with contempt: 10-12 “Two men went up into the temple to pray, one a Pharisee and the other a tax collector. The Pharisee, standing by himself, prayed thus: ‘God, I thank you that I am not like other men, extortioners, unjust, adulterers, or even like this tax collector. I fast twice a week; I give tithes of all that I get.’  13 But the tax collector, standing far off, would not even lift up his eyes to heaven, but beat his breast, saying, ‘God, be merciful to me, a sinner!’ 14 I tell you, this man went down to his house justified, rather than the other. For everyone who exalts himself will be humbled, but the one who humbles himself will be exalted.”

15-16 Now they were bringing even infants to him that he might touch them. And when the disciples saw it, they rebuked them.  But Jesus called them to him, saying, “Let the children come to me, and do not hinder them, for to such belongs the kingdom of God. 17  Truly, I say to you, whoever does not  receive the kingdom of God like a child shall not enter it.” Luke 18:9-17 English Standard Version

An interesting footnote in most Bibles tells us that the words where Jesus said: “The Pharisee, standing by himself, prayed thus” could also be translated as: “The Pharisee, standing, prayed to himself.” That would certainly fit in with what this parable was all about, how some people trust in themselves that they are the righteous ones – and look down on others, even with contempt. Self righteousness has been, and still is, the root of so much evil and harm in the word. We see it in groups like ISIS and the Taliban, we see it in political movements like BLM and LGBT, and, sadly, it’s also seen in Christians whose faith appears to rest more in their own dogmatism than in Christ. Many of the Pharisees in Jesus' day were examples of this religious self righteousness.

What do vs 10-12 suggest that those who trust in themselves are basing their assumptions on?

They focus on the outward observance of religious rules and rituals. Jesus wasn't saying that the man was wrong for not extorting others or committing adultery. And Jesus wasn't saying that we shouldn’t fast or give to the poor. But these are not things that can solve the real condition of what we are like on the inside. What led to the tax collector being justified before God? (vs 13)

He was so aware of how our sin separates us from God that he felt unworthy to even draw near to God, and to look Him in the face. And then his prayer was not of his merits and achievements – it was a plea for mercy. He wanted God to show him amazing grace! He was praying to God – the other man was praying to himself. He showed utter humility, the other sang his own praise.

I don't think it was coincidence that Luke followed up this parable with the incident in vs 15-16. What do Jesus' words in vs 17 tell us which show that there’s a danger of misplaced trust even for those who are His disciples?

While it may have been a case that they thought children “should be seen but not heard” – it could also be that they thought children weren't mature enough to understand spiritual matters - that children were not capable of trusting in the Saviour. The danger then is that, as Christians, we may be trusting in our trust rather than trusting in Christ. We may be viewing our own faith and understanding of the gospel as the reason why we are justified. That can easily lead to looking down on others who don't have the same depth of understanding as we think we have. Right theology is important – but if it doesn't lead to the humility of the tax collector Jesus spoke of in the parable, then we could end up 'praying to ourselves' too.

Apart from showing us that children are welcome to Christ, and that we should tell them from their earliest years all that Jesus said and did, we also see that we ourselves need a childlike simplicity and humility if we wish to enter God's kingdom. Our trust must not be in our intellect, or even our Christian lifestyle – it must be in Christ Jesus, and in the sacrifice He made for sinners. We need God’s mercy - not merits of our own.