Today is the National Day of Prayer, and it’s clear our nation needs prayer. You’ve heard the phrase “Prayer changes things” — but do we believe it?

The Apostle Paul told us to “pray without ceasing,” and James said “the effectual prayer of a righteous man accomplishes much.”

As Christians, we should place great value on prayer — both personal and national — because God does. But do we ever wonder why more people don’t pray and why we don’t see more answers to prayer?

Most Christians know and understand that prayer is important, and some pray faithfully for our nation and themselves — yet we may see few visible answers.

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If we assemble and pray for our nation, doesn’t it make sense to know what God requires when we pray?

There are four reasons God says He won’t answer some prayers.

1.) Praying with an unclean heart. Prayer can be powerful. It can move mountains — or it can move nothing.

Sadly, when most people pray, they just go through the motions with no power or results because their hearts are unclean. Psalms 66:18 says, “If I harbor sin in my heart, the Lord will not hear me.”

Unconfessed sin is fatal to effective prayer. The Psalmist further says that even if we sacrifice and cry out with great passion but hold sin in our heart, God won’t answer. He won’t even listen!

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Living in sin or harboring unconfessed sin guarantees unanswered prayers. In these perilous days of our nation, when few people actually pray, shouldn’t we who do look into our hearts first? Can God answer your prayers — or is sin preventing Him from even hearing you?

2.) Praying according to our will — not God’s. God wants us to pray, but He demands it be done His way, including for the right reasons. Scripture is clear: Answered prayer requires praying according to God’s will.

How often do we pray seeking only our desires? When we pray as God requires, He’ll answer. But if we don’t, He won’t hear us.

Jesus Christ prayed according to His Father’s will. Shouldn’t we?

Seeing our prayers answered demands obedient living, including a submissive attitude to God’s will. So, as Christ prayed, let us also finish with the words, “Nevertheless, not my will but thine be done.”

Powerful prayer will reflect seeking God’s will in our prayers.

3.) Praying without faith. How often do we come to God in prayer but don’t really expect Him to answer? Christ said in Matthew 21:22, “Whatsoever you ask in prayer, believing, ye shall receive.” Christ told His disciples that when people pray in faith, truly believing that God can answer, they would be able to do great things — even move mountains!

The opposite is also true. If there is little faith, there is little power.

Sometimes we don’t see answers to prayer because we don’t really believe God can or will answer us. Let’s pray in power and with faith

God will then answer just as He promised — and even move mountains.

4.) Praying selfishly. Because our leaders have so arrogantly and repeatedly rejected God’s rule nationally and so many individuals have rejected God’s authority personally, we’re in trouble and we need God’s help.

Living in sin, praying according to our own will, and praying with little faith will all prevent God from answering our prayers.

James 4:3 gives us a fourth reason. James says, “You ask and receive not, because you ask that you may consume it upon your lusts.”

Selfish praying will close God’s ears to our prayers. James makes it clear — when we pray selfishly, asking God for things to elevate our status in the world’s eyes, or hoping for more favor with our friends than favor with God, God won’t answer our prayers.

On this National Day of Prayer, may we pray with clean hearts, pray according to God’s will, pray with faith that God can move mountains, and pray selflessly.

It’s time to get serious about our praying.

Sam Rohrer is president of the American Pastors Network, a national network of pastors with constitutional and biblical teachings that discusses today’s pressing issues. He was a Pennsylvania lawmaker for 18 years and hosts the daily “Stand in the Gap Today” national radio program on more than 400 stations. He is also host of the “Stand in the Gap” national television program.