Aaron and Moses were depending on the power of God, so how did Pharaoh's sorcerers do the same thing?
Exodus 7:12
NASB - 12 For each one threw down his staff and they turned into serpents. But Aaron's staff swallowed up their staffs.
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The above answers are so complete - and so well supported by scripture that I'll just share my witness to the fact that prayer is not just "something that's good to do". It is good medicine. It is a stress reliever. It is a hope fortifier. It is soothing to the mind and spirit. It is free. Nobody but the Lord knows what's really going on in my life; so I know He'll direct my path in the way of righteousness.
I pray because I love God, and love to communicate with Him. He is always present in my thoughts; and therefore He is THE FIRST priority in the start, middle, and end of my day. I praise Him, and glorify Him because He is the source of all my strength. And His continuous blessings, grace and mercy are evidence that He hears and answers my prayers. Even when things are not going my way, I have peace in my spirit because my relationship with God is so strong. It would not be so strong if I didn't communicate with Him as much as I do.
I don't mean to say that I am on my knees in prayer every waking hour. I communicate with Him just as I would a loved one who lives with me (He does!). Once you feed yourself with His Word, acknowledge His presence in every aspect of your life, and have the faith that He Is a rewarder of those who diligently seek Him, prayer is like breathing. You don't have to think about it - it becomes a part of you.
I just live in peace, and confidence that the Lord God, His Son, the Living Word, and the Precious Holy Spirit are available to me. So I do my best to be available to them. I share my knowledge and appreciation of God's presence in my life when prompted by the Holy Spirit. I have discovered that joy in the Lord is contagious, and I share it with a smile, a joyful greeting, an encouraging word, and even silent prayer for someone I cannot converse with personally.
Prayer keeps me strong in the midst of diverse temptations, and sad circumstances. So, if you want the joy of the Lord to be your strength, stay "prayed up". It's a good thing!