I know! I know! You want to know what that means. Sukuma language meaning is, “If you just stand around, watching someone else doing a job, not offering to help, you are most likely be hurt or inconvenienced in some way”.
The example is that of thatching a grass roof. It is a dirty job! The grass is dry and, if the chaff and seed-heads are not combed out, that itchy stuff also floats downward. The person below, watching the roofer, is likely to get some chaff in his eye.
Now, for the application of the African saying. “[The one] standing and looking gets something [chaff?] in their eye”. The jibe is that he should be helping.
So much for the phrase and its meaning. It is mainly used when someone either:
1. Just stands around, watching someone else work and doesn’t help, as a warning of the danger of “just looking” and “lazyness” when there is something that needs to be done.
2. If someone watching someone else work is injured by something that happens it is their own fault. Better to “move on by”, without stopping and watching, than just stand around and do nothing.
Contrast this with the Scriptures, “Say not ye, There are yet four months, and then cometh the harvest? behold, I say unto you, Lift up your eyes, and look on the fields, that they are white already unto harvest.” John 4:35
There is work to be done; there are others involved in the work; don’t be one who stands by and watches what others are doing; be careful least that inaction on your part brings trouble or upset to you.