Usually, where there is smoke there is a fire.
But the smoke is just a sign; the reality is the fire.
But there may be times when there is just so much smoke that we may not be able to see the fire, as in when wet grass is being burnt.
For Moses, there was a smoke that was surrounding him, in the figurative sense.
His life was rather peaceful, he was married and has a family and spends his time looking after sheep.
He has almost forgotten about his people who were under slavery in Egypt.
It was a burning issue but the smoke had blurred his vision and he also may not want to think too much about it.
Then came the burning bush that aroused his curiosity and then he heard the call to deliver his people out of Egypt.
There are issues in our lives that are burning but we don't know where is the fire or may not know how to put out the fire.
But let us be humble and present these burning issues to the Lord and the Lord will show us what we need to do.