Answer
We come to God in prayer for a variety of reasons—to worship Him, to confess our sins and ask for forgiveness, to thank Him for His blessings, to ask for things for ourselves, and/or to pray for the needs of others. The Hebrew and Greek words most often translated “supplication” in the Bible mean literally “a request or petition,” so a prayer of supplication is asking God for something. Unlike the prayer of petition, which is praying on behalf of others, the prayer of supplication is generally a request for the person praying.
The Bible includes many prayers of supplication. Numerous examples are found in the Psalms. David’s psalms are filled with supplication for mercy in Psalm 4:1, for leading in Psalm 5:8, for deliverance in Psalm 6:4, for salvation from persecution in Psalm 7:1, and so on. When Daniel learned that King Darius had issued an edict prohibiting prayer to any god but the king, Daniel continued to pray to God with prayers of thanksgiving as well as prayers of supplication for His help in this dire situation.
In the New Testament, Jesus tells us to ask for our daily bread in Matthew 6:11, which falls into the category of a prayer of supplication. In addition, in Luke 18:1-8, Jesus teaches us not to give up praying for what we need. James says that: on the one hand we don’t receive because we don’t ask (James 4:2). On the other hand, we ask and don’t receive because we are thinking only of our fleshly desires (James 4:3). Perhaps the best way to approach supplications is to ask God in all honesty as children talking to their kind-hearted Father, but ending with "Your will be done" (Matthew 26:39), in full surrender to His will.
After describing the need to take up the “full armor of God” (Ephesians 6:13-17), the apostle Paul exhorted the Ephesians (and us) to remain alert and to pray in the Spirit, “making supplication for all the saints” (Ephesians 6:18). Clearly, prayers of supplication are part of the spiritual battle all Christians are engaged in. Paul further exhorts the Philippian church to relieve their anxieties by remaining faithful in prayer, especially prayers of thanksgiving and supplication. This, he concludes, is the formula for ensuring that “the peace of God, which passes all understanding, will guard your hearts and your minds in Christ Jesus” (Philippians 4:6-7).
Here we see another crucial aspect of the prayer of supplication—the necessity of faith in the Lord Jesus Christ. Those who belong to Christ also have the indwelling Holy Spirit who intercedes on our behalf. Because we often don’t know what or how to pray when we approach God, the Spirit intercedes and prays for us, interpreting our supplications so that, when we are overwhelmed by trials and the cares of life, He comes alongside to lend assistance with our prayers of supplication as He sustains us before the throne of grace (Romans 8:26).
