The Bible never explicitly says that worry is sinful, however, we can conclude this based on Scripture. Most worry, or anxiety, is a failure to trust God. The fact that God sent His only son to die for our sins, in order to restore fellowship between Creator and His creation, is proof of His powerful love for mankind.
“For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life.” John 3:16 (NKJV)
The Bible is God’s living Word. When we doubt the many promises found in Scripture, we are actually questioning God’s love for us. Our lack of trust reveals our lack of faith.
Doubt is a tool Satan uses to make us lack confidence in God’s Word and consider His judgment unlikely.
“For the Word of God is alive and active. Sharper than any double-edged sword, it penetrates even to dividing soul and spirit, joints and marrow; it judges the thoughts and attitudes of the heart. “ Hebrews 4:12 (NKJV)
Worry is largely based on fear. It is the anxiety caused when we think we will lose something or not receive necessary help. God wants our confidence to be in Christ Jesus, for our competence comes from God.
“ Such confidence we have through Christ before God.  Not that we are competent in ourselves to claim anything for ourselves, but our competence comes from God.” 2 Co 3:4-5 (NIV)
Worrying about things that we cannot change is a waste of time. Corrie ten Boom nailed it when she wrote, “Worry is like a rocking chair; it keeps you busy but gets you nowhere.” Praying for our needs and worshipping God for having met those needs, in His time, is much more productive. But to lay aside worry we must also lay aside doubt.
The Bible says that doubt is a destroyer of life. Seems pretty clear, right? Doubt = double-minded, unstable sin. If you have doubts, God isn’t pleased and you shouldn’t expect answers to prayer.
“But let him ask in faith, with no doubting, for he who doubts is like a wave of the sea driven and tossed by the wind.  For let not that man suppose that he will receive anything from the Lord” James 1:6-7 (NKJV)
Thankfully, Jesus offered help for worriers by reminding us of important truths in Matthew 6:25-34. First, we are of infinite worth to God. All of creation is significant, including every bird and flower. Knowing how He cares for even the smallest of His creatures should give us assurance that He will not neglect those who have been made in His image. The one who knows us best will, in all things, guide us toward His preferable future for our lives.
Next, Jesus asks a question. Can worry add a single hour to your life? No, in fact, it is likely to subtract hours and cause health problems. Worry is a lack of faith. Once we recognize our inability to resolve matters independent of God, we can put our future in His hands.
“Can any one of you by worrying add a single hour to your life?” Matthew 6:25 (NIV)
The remedy for doubt is faith, and faith comes by hearing the Word of God.
“So then faith comes by hearing, and hearing by the word of God.” Romans 10:17 (NKJV)
So, if doubt is causing anxiety in your life, start reading the Bible! Listen to teachings on the radio, and play worship music. Don’t try to take the reins from God thinking you can solve matters through your own strength. Why assume that the things beyond your control are your responsibility? Hand them over to God. It will free you from burdens beyond your ability to bear and provide better nights of sleep.
 “When you lie down, you will not be afraid; Yes, you will lie down and your sleep will be sweet.” Proverbs 3:24 (NKJV)