It can get frustrating when the same phrase in the original language is translated in a different way. That is what happens when the focus in the Gospel according to Mark turns toward parables.
In Mark 3:21, you get the idea that Jesus' family is calling him crazy. It is actually, literally, those around him, and this is the same designation that is made in Mark 4:10. This is the group that asked Jesus about the parables. And Jesus talks to them for a while. And, so, we have the text for this Sunday (Mark 4:26-34).
It is not too far a stretch to think of ourselves as 'those around Jesus'. And it is not too far a stretch for us to think that sometimes God is crazy for not doing what WE think he should be doing.
The growing seed and the mustard seed are good parables to remind us that God is at the heart of the growth. It is HIS kingdom. Unfortunately we can start to think that it is ours.
Sometimes the Gospel according to Mark ends a section on a negative note. The last verse of the account (Mark 16:8) does that in a way. The last verse of the text for this Sunday ends somewhat positively. The translation reads that Jesus 'explained everything' to his disciples privately. But one should not think that this solves all the problems the disciples had and that they had no difficulties for the rest of the account.
One might look at the word 'explained'. In one of the dictionaries (BDAG), the basic definition of the word is to release or set free. But its use in the New Testament is more knowledge related and means to explain, resolve, or settle. (It is essentially used only in 2 Pet 1:20, Mark 4:34, and Acts 19:39.)
That physical emphasis seems to be what is often emphasized elsewhere in this account. This understanding also reminds us that it is not about understanding the situation, but it is about believing in the One who was sent. We trust that He is the One who frees us from sin.