It seems prayers would be useless if the outcome is already determined. Unless we we say God knew you would pray for this or that and he gave a certain outcome.
God knows everything and knows the outcome of every possible combination of choices a soul will or could have made. He knows that if you pray for your family certain graces will come to them; He also knows that if you do not pray for your family certain graces will not come to them. About prayer, Archbishop Sheen explained that there are countless favors hanging from heaven on silken cords, and prayer is the sword that cuts them down.
An analogy should help. Three possible scenarios which God knows the outcome of:
A) A man hiking in the wilderness is destined to be gobbled up by the hungry lion, provided the man forgets to take his rifle.
**B) **The same man is destined to aim his rifle and pull the trigger to shoot the lion, provided he remembers to take his rifle.
C) The lion is destined to be killed by the bullet exiting the man’s rifle, provided the man’s wife prays that he not forget to load his rifle before he goes into the wilderness.
Thus it is true that we should never cease to pray, never cease to commend ourselves and our loved ones in prayer to God’s protection. Now read all the graces that flow into a person’s life, provided the daily rosary is prayed with devotion:
FIFTEEN PROMISES OF THE BLESSED VIRGIN TO CHRISTIANS WHO FAITHFULLY PRAY THE ROSARY
** 1. **To all those who shall pray my Rosary devoutly, I promise my special protection and great graces.
** 2. **Those who shall persevere in the recitation of my Rosary will receive some special grace.
** 3. **The Rosary will be a very powerful armor against hell; it will destroy vice, deliver from sin and dispel heresy.
** 4. **The rosary will make virtue and good works flourish, and will obtain for souls the most abundant divine mercies. It will draw the hearts of men from the love of the world and its vanities, and will lift them to the desire of eternal things. Oh, that souls would sanctify themselves by this means.
** 5. **Those who trust themselves to me through the Rosary will not perish.
** 6. **Whoever recites my Rosary devoutly reflecting on the mysteries, shall never be overwhelmed by misfortune. He will not experience the anger of God nor will he perish by an unprovided death. The sinner will be converted; the just will persevere in grace and merit eternal life.
** 7. **Those truly devoted to my Rosary shall not die without the sacraments of the Church.
** 8. **Those who are faithful to recite my Rosary shall have during their life and at their death the light of God and the plenitude of His graces and will share in the merits of the blessed.
** 9. **I will deliver promptly from purgatory souls devoted to my Rosary.
** 10. **True children of my Rosary will enjoy great glory in heaven.
** 11. **What you shall ask through my Rosary you shall obtain.
** 12. **To those who propagate my Rosary I promise aid in all their necessities.
** 13. **I have obtained from my Son that all the members of the Rosary Confraternity shall have as their intercessors, in life and in death, the entire celestial court.
** 14. **Those who recite my Rosary faithfully are my beloved children, the brothers and sisters of Jesus Christ.
** 15. **Devotion to my Rosary is a special sign of predestination.