Why not? We don't have any power to control the future. There are many threats to our well-being. How do we know if we will be healthy or sick? How do we know if we will have enough food, shelter, clothing? How do we know if we will have a job or not? How do we know if our loved ones will live or die?
We tend to worry.
But worry is the opposite of faith. We have no power to control the future, but the future is under control. We are safe in the care of God. Whatever He allows into our lives will come by His loving care for us. Whatever the difficulties we face, God is there as our sufficiency. He will never leave us or forsake us.
The Lord chides His disciples for their "little faith."
When they worry about food, drink and clothing...
(Matthew 6:30) Now if God so clothes the grass of the field, which today is, and tomorrow is thrown into the oven, will He not much more clothe you, O you of little faith?When their boat is in danger of sinking...
(Matthew 8:26) But He said to them, “Why are you fearful, O you of little faith?” Then He arose and rebuked the winds and the sea, and there was a great calm.When Peter starts to sink while trying to walk on water...
(Matthew 14:31) And immediately Jesus stretched out His hand and caught him, and said to him, “O you of little faith, why did you doubt?”This always used to bother me. Isn't it natural to worry about imminent death? Even though Jesus knows what He's going to do, how are the disciples supposed to know? It seems unfair to call them people of "little faith."
But Jesus was serious. He wanted them to know Him better and trust Him more. They needed to get over being worried, fearful and timid so they could be bold witnesses for Him.
That's what we need too. Continue to follow Jesus. Read and believe God's word. Commune with God in prayer. Know Him better and trust Him more. Have faith in God.
Plan well, work hard and be smart - and trust God. It is not your plan or your hard work or your brains that will supply your needs, but God's sovereign care for you. Rest in Him and be free from panic and terror and anxiety and angst and depression.
The world is out of your control and you don't know what is coming up next, but God is in complete control and is working everything out for His perfect plan. He won't drop you.