I read in the Scriptures of all the good things, promises, happiness, peace, comfort and more that the righteous are told they will enjoy, but when you consider their life, it is mostly filled with misery. So I ask, is it only in heaven that they will enjoy these things?
If you think about your question a moment, it implies that there are no earthly benefits to righteousness. In counting the cost of becoming a Christian, Jesus tells us, "Assuredly, I say to you, there is no one who has left house or parents or brothers or wife or children, for the sake of the kingdom of God, who shall not receive many times more in this present time, and in the age to come eternal life" (Luke 18:29-30).
Paul argued that disciplining yourself to be righteous has both immediate and long term benefits. "But have nothing to do with worldly fables fit only for old women. On the other hand, discipline yourself for the purpose of godliness; for bodily discipline is only of little profit, but godliness is profitable for all things, since it holds promise for the present life and also for the life to come. It is a trustworthy statement deserving full acceptance" (I Timothy 4:7-9).
As an example, after Job suffered so much at the hand of Satan, we read: "The LORD restored the fortunes of Job when he prayed for his friends, and the LORD increased all that Job had twofold. Then all his brothers and all his sisters and all who had known him before came to him, and they ate bread with him in his house; and they consoled him and comforted him for all the adversities that the LORD had brought on him. And each one gave him one piece of money, and each a ring of gold. The LORD blessed the latter days of Job more than his beginning; and he had 14,000 sheep and 6,000 camels and 1,000 yoke of oxen and 1,000 female donkeys. He had seven sons and three daughters. He named the first Jemimah, and the second Keziah, and the third Keren-happuch. In all the land no women were found so fair as Job's daughters; and their father gave them inheritance among their brothers. After this, Job lived 140 years, and saw his sons and his grandsons, four generations. And Job died, an old man and full of days" (Job 42:10-17).
Now you and I might not receive wealth from God, but as David pointed out: "For a day in Your courts is better than a thousand outside. I would rather stand at the threshold of the house of my God than dwell in the tents of wickedness. For the LORD God is a sun and shield; the LORD gives grace and glory; no good thing does He withhold from those who walk uprightly. O LORD of hosts, how blessed is the man who trusts in You!" (Psalms 84:10-12).
The reason is that righteousness guides us and helps us avoid the problems that destroy the wicked. "The integrity of the upright will guide them, but the crookedness of the treacherous will destroy them. Riches do not profit in the day of wrath, but righteousness delivers from death. The righteousness of the blameless will smooth his way, but the wicked will fall by his own wickedness. The righteousness of the upright will deliver them, but the treacherous will be caught by their own greed" (Proverbs 11:3-6).
While there are times of difficulties in everyone's life, it doesn't mean all of life is miserable. The book of Ecclesiastes was written to explain to us why God put us here on earth. Many people find it to be a depressing book because it calls so many things useless that most people think are important. But scattered through the book are statements about what is important in life:
"Nothing is better for a man than that he should eat and drink, and that his soul should enjoy good in his labor. This also, I saw, was from the hand of God. For who can eat, or who can have enjoyment, more than I? For God gives wisdom and knowledge and joy to a man who is good in His sight; but to the sinner He gives the work of gathering and collecting, that he may give to him who is good before God. This also is vanity and grasping for the wind" (Ecclesiastes 2:14-16).
"I know that nothing is better for them than to rejoice, and to do good in their lives, and also that every man should eat and drink and enjoy the good of all his labor-it is the gift of God" (Ecclesiastes 3:12-13).
"Here is what I have seen: It is good and fitting for one to eat and drink, and to enjoy the good of all his labor in which he toils under the sun all the days of his life which God gives him; for it is his heritage. As for every man to whom God has given riches and wealth, and given him power to eat of it, to receive his heritage and rejoice in his labor-this is the gift of God. For he will not dwell unduly on the days of his life, because God keeps him busy with the joy of his heart" (Ecclesiastes 5:18-20).
"Live joyfully with the wife whom you love all the days of your vain life which He has given you under the sun, all your days of vanity; for that is your portion in life, and in the labor which you perform under the sun" (Ecclesiastes 9:9).
"Rejoice, O young man, in your youth, and let your heart cheer you in the days of your youth; walk in the ways of your heart, and in the sight of your eyes; but know that for all these God will bring you into judgment. Therefore remove sorrow from your heart, and put away evil from your flesh, for childhood and youth are vanity" (Ecclesiastes 11:9-11).
Life is meant to be enjoyable and can be enjoyed, whether you have little or much.