Why did the disciples ask Jesus to explain the parable of the weeds after he had just told them two other parables?
Two views of why the disciples asked Jesus to explain the parable of the weeds after he had just told them two other parables:
The disciples were confused that a story about the kingdom of heaven included weeds, so they specifically asked about what they saw as the unresolved issue of the weeds.
Jesus likely spoke more parables, and also more explanations, than Matthew records. Matthew 13 gives a selection, with the explanations of the more difficult parables, likely assuming that readers could interpret the simpler parables themselves, once given a few examples.
Interpretation 1:
The disciples seemed perplexed by the fact that in a story about the kingdom of heaven, weeds could be present. And so, they specifically ask a question regarding what they regarded to be the unresolved issue of the weeds.1
Interpretation 2:
It is difficult to say why the disciples asked for an explanation of this parable rather than those of the mustard seed or leaven. In general, one may assume that Jesus spoke more parables and also explained more of them than Matthew records. In Matthew 13:1–58 the evangelist provided a selection and likely purposefully included, among the explanations, that of one of the most difficult parables. He likely assumed that his readers could interpret the simpler parables themselves once given a few examples.2
36 Then he left the crowds and went into the house. And his disciples came to him, saying, “Explain to us the parable of the weeds of the field.”