I have a dear friend who served as a missionary in Suriname for many years, but in his final years he was stricken with an illness that paralyzed him. At times he wondered why God allowed him to linger. He longed to depart and to be with his Lord.
Perhaps life is very hard for you or a loved one, and you are wondering why God has allowed you or your loved one to linger. When Jesus said He was going to heaven, Peter asked, “Lord, why can I not follow You now?” (John 13:37). You, like Peter, may wonder why entry into heaven has been postponed: “Why not now?”
God has a wise and loving purpose in leaving us behind. There is work to be done in us that can only be accomplished here on earth. Our afflictions, which are for the moment, are working for us “a far more exceeding and eternal weight of glory” (2 Cor. 4:17). And there is work to be done for others—if only to love and to pray. Our presence may also be for the purpose of giving others an opportunity to learn love and compassion.
So, though you may desire release for yourself or a loved one, to live on in the flesh can mean fruitfulness (Phil. 1:21). And there is comfort in waiting: Though heaven may be delayed, God has His reasons. No doubt about it!

Not so in haste, my heart!
Have faith in God, and wait;
Although He seems to linger long
He never comes too late. —Torrey
Our greatest comfort is to know that God is in control.