If only one could tell

If parents could tell from birth what exactly their little child would do for a living, then they would give it their best shot. If only every child knew what exactly would put food on their table at the end of the day, then they would not waste any time in irrelevant fields of study. But since we do not know, it is important to give in our best in everything we do. Hence, the Biblical injunction, whatever your hand finds to do, do it with all your might, for there is no thought or counsel in the grave where you will end up (paraphrased)