I’m currently preaching through the book of James at church and in my preparation I found these words from John MacArthur on why the Lord allows trials in the lives of His people to be of great encouragement.
1) First, it is to test the strength of our faith. – In many ways the Lord assists us in taking spiritual inventory by bringing trials into our lives to demonstrate to us the strength or weakness of our faith. (Ex 16:4; 2 Chron. 32:31; Luke 14:26; Hab. 3:17-18)
2) Second, trials are given to humble us, to remind us not to let our trust in the Lord turn into presumption and spiritual self-satisfaction. – The greater our blessings, the more Satan will tempt us to look on them as our own accomplishments rather than the Lord’s, or as our rightful due and to become proud rather than humble. (2 Cor. 12:7)
3) Third, God allows us to suffer trials in order to wean us from our dependence on worldly things. – The more we accumulate material possessions and worldly knowledge, experience, and recognition, the more we are tempted to rely on them rather than the Lord. (John 6:5-7; Ex 2:11-25; Heb. 11:24-26)
4) Fourth, a purpose of trials is to call us to eternal and heavenly hope. – The harder our trials become and the longer they last, the more we look forward to being with the Lord. (Phil. 1:23-24; Rom 8:18-25)
5) Fifth, a purpose of trials is to reveal what we really love. – Abraham’s willingness to sacrifice his son Issac not only proved his faith, but also his supreme love for the Lord. Nothing and no one else should be dearer to us than the Lord. (Gen 22; Deut 10:12; Luke 14:26)
6) Sixth, trials are given to teach us to value God’s blessings. – Our reason tells us to value the world and the things of the world, and our senses tell us to value pleasure and ease. But through trials, faith tells us to value the spiritual things of God with which He has blessed us abundantly–including His word, His care, His provision, His strength, and, of course His salvation. (Ps 63:3-7)
7) Seventh, the Lord uses trials to develop in His saints enduring strength for greater usefulness. – The Puritan Thomas Manton perceptively observed that “while all things are quiet and comfortable, we live by since rather than by faith. But the world of a soldier is never known in times of faith.” (2 Cor 12:10; Heb. 11:33-34)
8) Either, and finally, the Lord uses trials to enable us to better help others in their trials. – Jesus told Peter, “Simon, Simon, behold Satan has demanded permission to sift you like wheat; but I have prayed for you, that your faith may not fail; and you, when once you have turned again, strengthen your brothers. (Luke 22:31-32) (Heb. 2:28; 2 Cor. 1:3-6)
From, The MacArthur New Testament Commentary, James. p.17-21.