Mark 4:30-34

And He said, “How shall we picture the kingdom of God, or what parable shall we use to illustrate and explain it? [Matt 13:31, 32; Luke 13:18, 19] It is like a mustard seed, which, when it is sown on the ground, even though it is smaller than all the [other] seeds that are [sown] on the soil, yet when it is sown, it grows up and becomes larger than all the garden herbs; and it puts out large branches, so that THE BIRDS OF THE SKY are able to MAKE NESTS and LIVE UNDER ITS SHADE.” [Ps 104:12; Ezek 17:23; 31:6] With many such parables, Jesus spoke the word to them, as they were able to hear and understand it; and He did not say anything to them without [using] a parable; He did, however, explain everything privately to His own disciples.