God knows the end from the beginning. He is acquainted with the hearts of all men. He reads every secret of the soul. He knows whether those for whom prayer is offered would or would not be able to endure the trials that would come upon them should they live. He knows whether their lives would be a blessing or a curse to themselves and to the world. This is one reason why, while presenting our petitions with earnestness, we should say, "Nevertheless not my will, but Thine, be done." [LUKE 22:42.] Jesus added these words of submission to the wisdom and will of God when in the garden of Gethsemane He pleaded, "O My Father, if it be possible, let this cup pass from Me." [MATT. 26:39.] And if they were appropriate for Him, the Son of God, how much more are they becoming on the lips of finite, erring mortals!
The consistent course is to commit our desires to our all-wise heavenly Father, and then, in perfect confidence, trust all to Him. We know that God hears us if we ask according to His will. But to press our petitions without a submissive spirit is not right; our prayers must take the form, not of command, but of intercession.
There are cases where God works decidedly by His divine power in the restoration of health. But not all the sick are healed. Many are laid away to sleep in Jesus. John on the Isle of Patmos was bidden to write, "Blessed are the dead which die in the Lord from henceforth: Yea, saith the Spirit, that they may rest from their labors; and their works do follow them." [REV. 14:13.] From this we see that if persons are not raised to health, they should not, on this account, be judged as wanting in faith.
We all desire immediate and direct answers to our prayers, and are tempted to become discouraged when the answer is delayed or comes in an unlooked-for form. But God is too wise and good to answer our prayers always at just the time and in just the manner we desire. He will do more and better for us than to accomplish all our wishes. And because we can trust His wisdom and love, we should not ask Him to concede to our will, but should seek to enter into and accomplish His purpose. Our desires and interests should be lost in His will. GW 218, 219
When we pray for earthly blessings, the answer to our prayer may be delayed, or God may give us something other than we ask, but not so when we ask for deliverance from sin. DA 266
Now this is the confidence that we have in Him, that if we ask anything according to His will, He hears us. 1 John 5:14 (New King James Version)