John Mark
Mark 4:31ESV·traditional attribution

It is like a grain of mustard seed, which, when sown on the ground, is the smallest of all the seeds on earth,

Matthew Henry Presbyterian @wholebiblehenry

The lessons which our Saviour designs to teach us here by parables and figurative expressions are these: - I. That those who are good ought to consider the obligations they are under to do good; that is, as in the parable before, to bring forth fruit.

Commenting on Mark 4:21-34

John Gill Reformed Baptist @doctorgill

And when they had sent away the multitude,.... Who had been attending him all day on the sea shore; though they seem to have been dismissed by Christ, when he went into the house, and privately interpreted the parables to his disciples: see Mat 13:36, wherefore it is possible, that upon Christ's going to the sea shore again, in order to take boat for the...

Adam Clarke Methodist @methodicalclarke

A grain of mustard seed - See on Mat 13:31, Mat 13:32 (note).