Dividing one's time between the work of the kingdom and professional work is something that must be done with the guidance of the indwelling Holy Spirit Of God. The Lord God Almighty needs to ensure that everyone who is given an assignment knows the importance of getting it done, despite all odds.
You cannot assume that you have a valid excuse for failing to complete an assignment that you knowingly accepted. If circumstances become difficult, you can always call on Jesus Of Nazareth to assist you, assuming that you have been seeking guidance from the indwelling Holy Spirit Of God. Moreover, nor can you assume that if others fail to do their part, you too can cheat destiny, and fail to do your part.
The Lord God Almighty will always reward you for any and all circumstances that make your assignment more difficult than was expected. More importantly, you can ask the Lord for additional rewards if you feel the need to do so. Equating assignments from God with assignments you receive on a job may be a practical way of looking at your circumstances, but assignments from God demand greater diligence.
The Lord God Almighty El Shaddai