God created human beings with limitations. We can only carry or juggle a limited amount of items, and our bodies can only grow so tall. The dimensions of our bodies are different yet all measurable by height, weight and volume. There is only so much information we can retain in our minds from a conversation or movie. Whatever can be stretched can also be broken or ruptured, and even the most fit professional athletes and labourers are no exception.
I have learned when I am easily provoked by a small thing it can be due to carrying a heavy mental load. Unresolved conflict within me, awareness of troubles others are experiencing, bad news or unexpected obstacles--really any and every little thing--can give rise to overwhelming feelings that stir aggression, frustration and depression. Peter exhorted believers to be submissive to God and one another, being clothed with humility because "God resists the proud, but gives grace to the humble." He said in 1 Peter 5:6-7, "Therefore humble yourselves under the mighty hand of God, that He may exalt you in due time, 7 casting all your care upon Him, for He cares for you."
Followers of Jesus are commanded to be casting all our care upon Jesus because He cares for us. There are countless things we can care about: we can be emotionally, financially and physically dependent upon them. Peter urged believers to keep casting these cares upon Jesus, not like a fisherman casts out a hook or lure with intent to reel it back to himself, but to throw our anxieties and worries upon Jesus for good. Why? Because Jesus cares for us. Jesus is not worried or anxious about us at all, for this "care" is a different word in the Greek that means "to be an object of care, concern." Worry and anxiety is a symptom of our natural weakness and inability to do anything to help ourselves or others. Instead of exalting ourselves we are called to humble ourselves under the mighty hand of God, knowing the smallest burden is too heavy for us to bear in our own strength.
It seems ironic to cast away our cares, for aren't cares evidence of us caring? Aren't we supposed to care? The truth is, carrying burdens we ought to cast upon Jesus is evidence of our carelessness. It is evidence we have neglected to guard our hearts and chosen for a season not to walk by humble faith in our awesome Saviour who cares for us. Instead of condemning us for our forgetfulness or rejecting us God remains merciful, gracious and compassionate towards us. He knows our weakness, limitations and foolishness. God's hand is mighty to save and deliver us by His grace. Knowing God cares and does everything gives us great confidence to throw all our anxieties and worries upon Him. We give Him all the feelings, things and circumstances we cannot do anything about, and thus we by faith invite Him to do His wonders concerning those things in His time and way.