This is fact.
Whether we pray to god or not, whether we perform remedies like wearing gemstones, crystal healing, reiki, chanting mantras etc, karma will give us what it has to, or rather what we deserve.
Even consulting an astrologer, palmist,pyschic/tarot reader will happen only when karma decides.
According to astrology, the ruling planets (moon sign owner, day owner, ascedent owner, owner of constellation in which moon is placed) match to the ruling planets at your time of birth.
This rule of Hora Astrology itself proves that karma takes its toll when it has to.
You will only know when you have to know. Before that you will meet people who will misguide you. Again this is controlled by karma.
God acts as an agent through planets,humans around us, etc, giving us results of our karma.
This is not to discourage anyone trying to perform remedies to control their problems, but to emphasize that remedies are like umbrellas trying to protect us from karmic influences like sun,rain etc.
But if our bad karma is more stronger, it can cause heavy wind which can take away our umbrella.
Everything depends on balancing equations of karma. If good karma is more than bad karma, we enjoy comforts and vice versa.
Only in exceptional cases god decides to overtake karmic influences for his/her devotee but it will happen for thos who have reached peaks in devotion and have completely surrendered to god.
Rest all have to pass through karma and its effects.