By the words "believe that ye receive them": we understand, expect God to give them to you. But it is at this point that so many of God's people fail oftenest in their prayer lives. There are three chief things to be attended to in prayer.
First, make sure that you are asking for something that is in accordance with God's Word: see 1 John 5:14. But right here, the devil will foil you unless you are upon your guard. He will come as an angel of light and preach a sermon to you on God's holy will. O yes, the devil is quite capable even of that! It is our privilege and duty to know what God's will is! "Wherefore be ye not unwise, but understanding what the will of the Lord is" (Eph. 5:17). It is the revealed will of God which is in view in these passages, for with His "secret" will, we have nothing to do; that is none of our business.
God's revealed will is made known in His Word. Fix this in your mind; never allow Satan inject a thought (Eph. 4:27) to shake you thereon, that everything God has commanded you to do, every precept and exhortation addressed to you, is "God's will" for you, and is to be turned into prayer for enabling grace. It is God's will that you should be "sanctified" (1 Thess. 4:2), that you should "rejoice" (Phil. 4:4), that you should "make your calling and election sure" (2 Pet. 1:10), that you should "grow in grace and in the knowledge of the Lord" (2 Pet. 3:18).
Second, having made sure that what you are praying for is according to God's revealed will, then plead His promises, such as Matthew 7:7, Philippians 4:19, etc. Plead them in the name of Christ, asking God to give you the "desires of thine heart" (Ps. 37:4) for Christ's sake, that He may be honored in and by a Godly walk from you, and that His people may be helped and encouraged by your example. Those are pleas which God cannot deny.
Third, and this is what we would earnestly and lovingly press upon the Christian reader: Expect God to do what you have asked. Unless there is an expectancy, faith is not fully in exercise. It is this expecting from Him which honours and pleases God, and which always draws down from Him answers of peace. There may be some difficulty, problem, trial, looming ahead of you, which assumes the proportions of a mountain. Never mind that: do not let it depress, discourage, or dismay you. Praise God it stands written in the eternal Word of Truth, "Verily I say unto you, If ye have faith and doubt not...ye shall say unto this mountain be thou removed, and be thou cast into the sea; It shall be done" (Matthew 21:21). Notice carefully, it is not "If thou doubt not and have faith, "but if ye have faith" and then (while you are awaiting God's answer) "doubt not", but continue the fulfillment of His promise. When you first get down on your knees, beg God in the name of Christ and for His own glory's sake, to work in you by His Spirit that expectancy of faith which will not take "NO" from Him; which reverently, but confidently says, "I will not let Thee go, except Thou bless me" (Gen. 32:26). That is what honours God, that is what pleases Him, that is what obtains answers from Him.
"A friend at court!" No doubt that expression is more or less familiar to the older readers, but it has almost dropped out of use in this generation. It denoted that one had a friend possessing influence with another in authority, and using it on my behalf. How unspeakably blessed to know that the Christian has a friend at court, the Court of Heaven; "A friend that sticketh closer than a brother." He has the ear of God, for on earth He declared "Thou hearest me always" (John 11:42). Then, make use of Him, and ask Him to present them to His Father and your Father, accompanied by His own all-prevailing merits; and, if they are for God's glory and thy (real) good, be fully assured that they shall be granted. Thus will Christ be honored and your faith strengthened.