There are two instances in Scripture—that I’m aware of—when God told someone not to pray, for He would not hear their prayer. Moses is the first example, for though he’d been faithful to God most of his life, he was told by the Lord he’d not enter the land promised to Israel because of his disobedience as a leader when he struck the rock (Num. 20:8-12). Moses pleaded with the Lord, saying, “Let me, I pray, cross over and see the fair land that is beyond the Jordan, that good hill country and Lebanon. But the LORD was angry with me on your account, and would not listen to me; and the LORD said to me, ‘Enough! Speak to Me no more of this matter’” (Deut. 3:25-26). God’s decision concerning Moses was final. Moses would not enter the Promised Land, for the Lord said, “Go up to the top of Pisgah and lift up your eyes to the west and north and south and east, and see it with your eyes, for you shall not cross over this Jordan” (Deut. 3:25-27; cf. Deut. 1:37; 31:1-2). God explained to Moses why He would not hear his prayer, saying, “because you broke faith with Me in the midst of the sons of Israel at the waters of Meribah-kadesh, in the wilderness of Zin, because you did not treat Me as holy in the midst of the sons of Israel” (Deut. 32:51). No amount of prayer would change God’s mind, so He told Moses to stop praying about it.
The second example is the prophet Jeremiah. God told him not to pray for his fellow Israelites. Three times God told Jeremiah, “do not pray for this people, and do not lift up cry or prayer for them, and do not intercede with Me; for I do not hear you” (Jer. 7:16; cf. 11:14; 14:11). The reason behind God’s command was that He had decided to judge and punish His people (Jer. 7:20) because they’d repeatedly broken their covenant with Him by disobeying His commands and pursuing other gods, which He had forbidden (Ex. 20:2-4; cf. Ezek. 20:4-24). Israel’s idolatry was terrible in Jeremiah’s day and included human sacrifice, as many caused their children to be burned alive (Jer. 19:4-5; cf. Ezek. 16:20-21; 20:25-26, 31). Over and over again, Israel disobeyed God’s commands and would not change their behavior (Jer. 7:21-26; 11:1-13). Though Jeremiah had repeatedly spoken God’s Word to them for over two decades (Jer. 25:3), the people openly defied His message, telling him, “As for the message that you have spoken to us in the name of the LORD, we are not going to listen to you!” (Jer. 44:16). Their hearts were hardened to God’s Word. If Israel had listened to God and turned back to Him from their idolatry, God would have reversed His discipline and provided blessing instead (Jer. 7:3-7). Until they changed their ways, no amount of prayer was going to change their situation. God would not be moved by their pleas, or the petitions of His prophets.
The New Testament teaches that God will discipline His disobedient people (Heb. 12:6; Rev. 3:19; 1 Cor. 11:32), even to the point of death (Acts 5:1-11; 1 Cor. 11:27-30, 1 John 5:16-17). However, there are no examples in the New Testament of God telling anyone not to pray. Instead, we are commanded to be “devoted to prayer” (Rom. 12:12; cf. Col. 4:2), to “pray at all times in the Spirit” (Eph. 6:18), and to “pray without ceasing” (1 Thess. 5:17; cf. Luke 18:1). This means the believer is to look to God always for wisdom and strength to do His will, lifting others before His throne of grace, requesting He will intervene as we ask, for His glory and their benefit.
 God had formed a covenant (בְּרִית berith) with the nation of Israel after He’d delivered them from Egyptian captivity (Ex. Chapters 3-14). The nation of Israel became a theocracy, and God gave them a total of 613 commands that were to guide their relationship with Him and others. God promised to bless Israel if they abided by the stipulations of the covenant (Deut. 28:1-14), and He promised to curse them if they did not (Deut. 28:15-68). God was being faithful to His word.
 The sin of idolatry was widespread in Jeremiah’s day, including Israel’s king, princes, and elders (Jer. 44:17), down to the basic unit of society, the family (Jer. 7:18). It’s an evil thing when parents lead their children away from righteousness and into gross immorality.
There are two statements I hear people make about prayer that are incorrect: 1) there’s power in prayer, and 2) prayer changes things. Both statements give undue authority to the one who prays. Biblically, the power lies in the One who answers the prayer, and He alone reserves the right to change things if He wills. God answers prayer, but He does so according to His sovereign will. Sometimes He says yes, sometimes no, and sometimes wait. It is good to remember that a prayer delayed is not necessarily a prayer denied. Sometimes we just need patience.
Prayer is discussion with God. It is motivated by different causes and takes different forms. Most often prayer is an appeal to God to change a difficult or helpless situation. Sometimes God changes our situations as we request (i.e., concerning employment, health, finances, family matters, etc.), and sometimes He leaves the difficult situation and seeks to change our attitude (2 Cor. 12:7-10). When God does not remove a difficult situation as we request, then He intends for us to deal with it by faith (Jam. 1:2-4). God uses difficult situations to remove pride (Dan. 4:37; 2 Cor. 12:7-10), and to develop our Christian character (Rom. 5:3-5). It’s almost always the case that we prefer God change our circumstances rather than our attitude; and yet, it seems both biblically and experientially that God prefers to do the opposite. Though the Lord is concerned about our difficult situations, He’s more concerned with developing our Christian character than relieving our discomfort. However God chooses to answer, He has His reasons and they always glorify Him. A challenge to us is to trust that His plan is better than ours, wherever it happens to lead us, or however difficult the journey becomes.
Prayer is for believers, for one can address God as Father only as a member of the family of God (John 1:12; Gal. 3:26). Jesus prayed often, both publicly and privately (Matt. 11:25-26; 14:23; 19:13; 26:36; Mark 6:46; Luke 5:16; 6:12; 9:28; 10:21; 22:41-42; John 11:41-42; 12:27-28; 17:1-26), and His prayer life was so noticeable, that His disciples asked Him to teach them to pray (Luke 11:1-4; cf. Matt. 6:9-13). For the Christian, prayer should be directed to God the Father (Matt. 6:6; Luke 11:2; Eph. 5:20; 1 Pet. 1:17),in the name of Jesus (John 14:13; 15:16), and in the Holy Spirit (Eph. 6:18; Jude 1:20). Praying in the name of Jesus is not a magic formula that makes our prayers acceptable to God; rather, it means our request is consistent with Jesus’ character and will (1 John 5:14-15). Praying in the Spirit means we pray as the Spirit leads according to Scripture. It is interesting to note that both God the Holy Spirit and God the Son offer intercessory prayers for us to God the Father (Rom. 8:26; Heb. 7:24-25).
Some of the different types of prayer found in Scripture include: request (Phil. 4:6; Eph. 6:18), thanksgiving (John 11:41; Phil. 4:6), submission (Luke 22:41-42), faith (Jam. 5:15), imprecation (Ps. 58:6-8; 69:23-28), and intercession (Acts 12:1-5). The best prayers seek to glorify God above all else. Moses provides a model prayer in Exodus 32:7-14 where he prayed on behalf of His people, Israel, that God would not pour out His wrath on them because of their idolatry (Ex. 32:1-6). Moses’ prayer to God starts by identifying Israel as “Your people” whom He had rescued from Egyptian bondage (Ex. 32:11). Israel was not just any people, but God’s chosen nation, who had already tasted of His great grace and compassion. After citing God’s deliverance, Moses then argued with God to withhold His wrath for two reasons: First, if God destroyed Israel, then His reputation among the pagan nations would be tarnished (Ex. 32:12). Moses sought to protect God’s reputation in the eyes of others, even unbelievers, and to uphold His glory above self-interest. Second, if God destroyed Israel, He would be in violation of the promises He’d made to Israel’s forefathers, Abraham, Isaac, and Israel (Ex. 32:13). Moses did not want others to see God as one who fails to keep His promises. Moses’ prayer was heard and God relented of the judgment He intended to bring on His people because of their sin (Ex. 32:14).
When God Does Not Hear Our Prayers
There are some things in life that God conditions on prayer (Jam. 4:2), but praying is no guarantee He’ll grant our request. Being a righteous God, He only hears the prayers of those who seek to know Him and do His will. The apostle Peter writes, “For the eyes of the Lord are upon the righteous and his ears are open to their prayer. But the Lord’s face is against those who do evil” (1 Pet. 3:12). The apostle John writes, “This is the confidence which we have before Him, that, if we ask anything according to His will, He hears us. And if we know that He hears us in whatever we ask, we know that we have the requests which we have asked from Him” (1 John 5:14-15).
Biblically, there are several reasons why God does not answer the prayer of believers: lack of faith (Jam. 1:5-8), worship of other gods (Jer. 1:16; 11:12-14), failure to take in Bible teaching (Prov. 1:24-31; 28:9; Zech. 7:11-13), selfishness (Jam. 4:2-3), carnality (Ps. 66:18; Mic. 3:4; Isa. 1:15; 59:1-3), lack of harmony in the home (1 Pet. 3:7), pride and self-righteousness (Job 35:12-13), and lack of obedience (Deut. 1:43-45; 1 John 3:22; 5:14). All of these failings can be corrected as the believer learns God’s Word and lives obediently by faith. Failure to learn God’s Word and/or apply it results in self-harm, much like a child who will not listen to her parents, but repeatedly keeps reaching for the hot flame because it’s pretty. God’s commands are designed to bring blessing, either by teaching us to avoid that which is harmful, or to pursue that which is helpful.
The apostle Paul reveals a situation when God refused to answer his prayer. Paul was struggling with something he called his “thorn in the flesh” (2 Cor. 12:7). We don’t know what it was, except that it caused him great hardship. Paul asked God to take it away, saying, “I implored the Lord three times that it might leave me” (2 Cor. 12:8). Paul uses the Greek verb παρακαλέω parakaleo, which in this context means “to make a strong request for something.” Paul was pleading with God to remove his problem, but God said no. The Lord had a reason for it to be there, and He told Paul, “My grace is sufficient for you, for power is perfected in weakness” (2 Cor. 12:9a). Paul did not like being weak. He did not like feeling helpless about this thing that caused him discomfort. But Paul’s thorn, however difficult it was to him, kept him close to God, and that’s what God wanted. It’s as though God were telling Paul, “Paul, I know you don’t like your suffering, but the very thing you don’t like is what keeps you close to me, and the strength of our fellowship is more important than the alleviation of your discomfort.” Suffering is our friend when it keeps up humble and close to God. When Paul understood this, his attitude changed, and he accepted his suffering and praised God for it. Paul said, “Most gladly, therefore, I will rather boast about my weaknesses, so that the power of Christ may dwell in me. Therefore I am well content with weaknesses, with insults, with distresses, with persecutions, with difficulties, for Christ’s sake; for when I am weak, then I am strong” (2 Cor. 12:9-10). This is a faith response, for it could never be born out of our emotions.
Prayer is a blessing we enjoy as believers as we can come before God’s throne of grace and make requests. As Christians, we are to “pray at all times in the Spirit” (Eph. 6:18), and to “pray without ceasing” (1 Thess. 5:17; cf. Luke 18:1; Rom. 12:12; Col. 4:2). As we advance toward spiritual maturity, God will occupy our thoughts in all matters, and prayer will come more and more naturally. And, like Moses, we will seek God’s interests above our own and pray according to His will.
 Scripture reveals, “Whatever the LORD pleases, He does, in heaven and in earth, in the seas and in all deeps” (Ps. 135:6), for “He does according to His will in the host of heaven and among the inhabitants of earth” (Dan 4:35), declaring, “My purpose will be established, and I will accomplish all My good pleasure” (Isa. 46:10).
 The most common words in the Bible translated prayer are תְּפִלָּה tephillah (Job 16:17; Ps. 65:2) and προσευχή proseuche (Luke. 19:46; Acts 12:5), which simply speak of the act of prayer. Other words include פָּלַל palal – to intervene as a mediator (Gen. 20:7; Job 42:8), לַחַשׁ lachash – a whispering prayer (Isa. 26:16; 29:4), שָׁאַל shaal – to ask, inquire (Isa. 7:11; 45:11), עָתַר athar – a prayer related to sacrifice (Job 33:26), δέησις deesis – an urgent request (Eph. 6:18), and ἔντευξις enteuxis – simple prayer, childlike prayer (1 Tim. 2:1). The word αἰτέω aiteo is not translated as prayer, but is clearly used when making requests to God (Matt. 7:7; John 14:13).
 The general agreement among theologians is that God does not hear the prayers of unbelievers, for they are not God’s children but belong to Satan. Jesus said of unbelieving Jews, “You are of your father the devil” (John 8:44). Logically, one cannot call God his Father if He is not. In another place, a man who had been healed by Jesus said to the Jewish religious leaders, “We know that God does not hear sinners; but if anyone is God-fearing and does His will, He hears him” (John 9:31). However, there does seem to be at least one occasion in which God heard the prayer of an unbeliever who was seeking Him for salvation (e.g. Acts 10:1-2, 30-31; 11:14). It could be that if an unbeliever seeks God for salvation, as Cornelius did, then His prayers for salvation are answered.
 Although there is at least one petition in the NT directed to Jesus (Acts 7:59-60).
 The Greek preposition ἐν can mean, “in” “by” or “with” the Spirit. Hoehner translates the prepositional phrase ἐν παντὶ καιρῷ ἐν πνεύματι as “at every opportunity or occasion in the Spirit” (Harold Hoehner, Ephesians: An Exegetical Commentary, Grand Rapids, Mich.; Baker Academic, 2002, p. 856). Hoehner further states, “In the immediate context [of Eph. 6:18], praying in the Spirit may well be connected to the sword of the Spirit. The sword of the Spirit is, on the one hand, God’s spoken word to put His enemies to flight and, on the other hand, the believer’s utterance to God in prayer in the power of the Holy Spirit to aid in the struggle against the evil powers” (p. 857).
 Imprecatory prayers were valid under the Mosaic Law where obedient Israelites could expect God to dispense justice to their enemies (Deut. 28:7). These types of prayers are not valid for Christians because we are not under the Mosaic Law (Rom. 6:14). We are commanded to pray for our enemies that God will bless them (Matt. 5:44-45; Luke 6:28, 35; cf. Rom. 12:17-21; 1 Thess. 5:15; 1 Pet. 3:9). If God dispenses judgment upon our enemies, He will do so at His discretion and not ours (Rom. 12:17-19; 2 Thess. 1:6).
 God’s deliverance was not based on any righteousness found in Israel, for He describes them as a “stubborn” and “rebellious” people who keep defying Him, in spite of His goodness (Deut. 9:6-7).
 William Arndt et al., A Greek-English Lexicon of the New Testament and Other Early Christian Literature (Chicago: University of Chicago Press, 2000), 765.