In Luke 18:9-14 (NET) we read the following: 9 “Jesus also told this parable to some who were confident that they were righteous and looked down on everyone else.
10 “Two men went up to the temple to pray, one a Pharisee and the other a tax collector. 11 The Pharisee stood and prayed about himself like this: ‘God, I thank you that I am not like other people: extortionists, unrighteous people, adulterers — or even like this tax collector. 12 I fast twice a week; I give a tenth of everything I get.’
13 The tax collector, however, stood far off and would not even look up to heaven, but beat his breast and said, ‘God, be merciful to me, sinner that I am!’
14 I tell you that this man went down to his home justified rather than the Pharisee. For everyone who exalts himself will be humbled, but he who humbles himself will be exalted.”
The very awareness of our need for mercy — to the extent that we can hardly bring ourselves to ask for it — is precisely the awareness that God readily and superabundantly responds to with mercy.
Conversely, it is the lack that awareness of needing mercy that keeps us alienated from God and under condemnation.
In other words, at the root of what separates us from God is a dismissive attitude towards how profoundly self-regarding our every thought, word, and deed actually is. We turn a blind eye to that, and end up suppressing the truth of how much we need mercy. Hence, no mercy is forthcoming.
That’s why everything Jesus came to do for us begins in us only when we are poor in spirit — that is — when we admit that we are spiritually bankrupt and that God's mercy is our only hope. For such individuals is the kingdom of heaven.