"Hitherto have ye asked nothing in my name: ask, and ye shall receive, that your joy may be full." (John 16:24)
Jesus promised that "whatsoever ye shall ask the Father in my name, he will give it you" (John 16:23). This condition for answered prayer and its resulting fullness of joy is not just a formula with which to end a prayer. "In my name" implies representing Him and what He stands for, so that our prayer could truly be His prayer as well.
For example, our prayer must be in His will. "If we ask any thing according to his will . . . we know that we have the petitions that we desired of him" (1 John 5:14-15).
We need also to recognize that God's great purpose in creation is of higher priority than our own personal desires, so this should be of first order in our prayers. Jesus said: "When ye pray, say, Our Father. . . . Thy kingdom come. Thy will be done, as in heaven, so in earth" (Luke 11:2). We can also pray for our own needs, of course, especially for God to "deliver us from evil" (Luke 11:4), the closing request in His model prayer.
It is good to seek God's wisdom in all our decisions and undertakings, so that we can be confident we are indeed in His will, but our request for such guidance must be sincere and in willingness to act on His answer. "If any of you lack wisdom, let him ask of God. . . . But let him ask in faith" (James 1:5-6). And it should be obvious that the request be made with a clear conscience before God. "If I regard iniquity in my heart, the Lord will not hear me" (Psalm 66:18).
But when we are indeed confident that we are praying "in His name" with all that this implies, then we should pray earnestly, for "the effectual fervent prayer of a righteous man availeth much" (James 5:16), and when the answer comes—as it will, in God's time—then our joy indeed will be full! HMM