The children's lesson is a novelty within the Divine Service. For almost the entirety of Christendom, the Church met without a children's lesson as part of the Divine Service.
It should be noted that the Bible neither commands nor forbids children's lessons. Although, proponents for children's lesson get close to accusing those who do not practice them as sinning against children. They will cite the women bringing the children to Jesus for him to bless them, and especially Jesus rebuking the apostles for keeping them away. Jesus said, “Let the little children come to me, and do not hinder them, for the kingdom of heaven belongs to such as these" (Matthew 19:14). The women did not bring their children to Jesus during synagogue worship. So, to equate this verse with a children's lesson is a bit misleading.
But if anyone insists on equating Jesus' blessing the children with children's lessons, then perhaps we should consider the earlier part of this reading: "Then people brought little children to Jesus for him to place his hands on them and pray for them" (Matthew 19:13). Is everyone comfortable with the pastor laying his hands on the children? In our modern climate, I fear legal charges could arise.
I have heard some people go so far as to say, "If a church does not have children's lessons, they don't care about the children." That charge is pure manipulation. It also condemns centuries of churches and pastors who never had them.
I opt to not include children's lessons in the Divine Service. There are a number of reasons for this. In no particular order, they include:
1) It segregates part of the congregation.
Having a portion of the service for just one segment of the congregation is divisive. If there is a lesson tailored to children, what about the teens? What about twenty-somethings? What about those newly married or recently widowed? Doesn't Jesus have a special message just for them?
The Divine Service is where the entire family of God joins together for worship, regardless of sex, age, marital status, and so forth. All sing together, pray together, and listen together. As the children grow older, they will gain more from the service. And they probably are getting more out of the service than parents realize.
2) There are already many children's lessons.
St. John's is blessed to have a Lutheran elementary school in which Bible History lessons are taught daily. There are also weekly chapel services. And there is Sunday School. These lessons are already tailored to their age levels.
If the parents are eager for the children's lesson to take place, I offer this solution: The parents can talk to their children about the sermon at home. This reinforces for the entire family the theme for the day, and it teaches the children that the parents consider the sermon and the service worthy of meditation beyond Sunday morning.
3) The children's lesson is a distraction from the liturgy.
The children's lesson interrupts the flow of the service as the pastor waits for children to come down from all parts of the sanctuary and settle in. After the lesson, the children return to their seats. Depending upon how long the pastor takes to teach the lesson, it is a five-minute break from the liturgy. If a children's lesson is necessary, it can be done outside of the liturgical order. And it is (cf point #2).
4) The children's lesson teaches the children that the rest of the service is not for them.
This is the most grievous lesson learned from having children's lessons. The children are summoned for a portion of the service which is "just for them." If that part is for them, by implication the rest is not. Why pay attention to the sermon when they already got their part done?
Sadly, adults have also remarked that they get more out of the children's lesson than they do the sermon. I suppose this is to be understood as an endorsement of the children's lesson. I would consider it an indictment, either of the pastor delivering a poor, incoherent sermon or of the listener not wanting to put in the effort of intentional listening. Sesame Street is easier to comprehend than 60 Minutes, but I hope adults would recognize that 60 Minutes has more substantive content.
5) The children's lesson is a time for amusement.
Another appeal for the children's lesson is the response that comes from children when questions are asked of them. After all, Kids Say the Darndest Things. Everyone looks forward to a chuckle. But if we come to church looking for a chuckle, we have missed the point of the Divine Service. The entire Divine Service is a time when we stand in the presence of our Lord. This is holy ground. Whenever people encountered our Lord in the Bible, no one was yucking it up. So, this levity is out of place for sinners yearning for God's mercy. There is a time and place for amusement. The Divine Service is not it.
Every practice in the Divine Service deserves to be evaluated. Some practices demonstrate reverence and avoid frivolity. Other practices detract from the sense of awe and glory that is worthy of our Lord. Not all practices are in the best interest of teaching the Christian faith, even if they are not strictly forbidden.

