بسم الله الرحمن الرحيم
In Arabic, the word “tawakkal” is translated as rely upon. This doesn’t quite capture the whole meaning. When you give someone “wakala” [the noun], you are giving them a power of attorney to act on your behalf. Now, you would never give a power of attorney to just anyone. If they have these three characteristics, you would be most at rest:
1) they are trustworthy
2) they know how to deal with the matter you’ve entrusted to them
3) they care about your welfare
That feeling of trust and confidence that you have in a person who these characteristics is the same feeling you should have with God. He is telling you to rely upon the Ever-living who never dies. He will never you. He has no weaknesses. Whatever you are worried about is safe with Him.
Strive, because we are asked to strive. But you know that everything is in His Hands. So don’t you worry. Because He is your wakeel.