2nd Temple Judaism looked for the ‘kingdom of God’ in a variety of ways. To the rich and powerful and those who colluded with Rome it had in some sense arrived, others longed for the in breaking of God’s reign but did not work towards it due to the tiresome and desperate nature of day to day existence. Others actively sought the arrival of the reign of YHWH through asceticism and Torah allegiance. Still others sought for the kingdom through the zealous and violent acts.
Jesus disciples tried to keep parents (presumably) from bringing their children to Jesus for a blessing. No doubt these parents had heard about the mighty acts of Jesus, of his great wisdom and insight.
Jesus responds by welcoming the children to himself and by using this as an opportunity to talk about the kingdom of God. I want to note a few things from this.
1) Children had no claim or status.
“Children in antiquity, who had no control, no claim, and no status, could welcome whatever came their way with open arms, not because they were innocent and trusting, but because they had nothing to lose and everything to gain. According to the Markan Jesus, people enter God’s realm, not in a proud triumphal procession, but in complete vulnerability, with no claim to any rights or status. It was not what the disciples had in mind, and the next incident proves even more devastating to their preconceptions. “
Dowd, S. E. (2000). Reading Mark : A literary and theological commentary on the second Gospel. Reading the New Testament series (104). Macon, Ga.: Smyth & Helwys Publishing.
2) The kingdom of God is to be received. It is nothing something which can be taken by force but is a gift of God.