When Jesus prayed, that which He prayed for was exactly what the will of the Father was. Only once did Jesus pray that “If it be possible” (Matt 26:39) and even then He knew what the Father’s will was. All other times His prayer was exactly what the Father wanted and so it was not just in harmony with God’s will, but it was the expression of that will, so what Jesus prayed for were in fact “promises and prophecies.” (Maclaren) What He prays for is going to happen and the only thing that can keep it from happening is the will of man refusing it.

Matthew 26:39  Going a little farther, he fell with his face to the ground and prayed, “My Father, if it is possible, may this cup be taken from me. Yet not as I will, but as you will.”

Jesus has expressed this thought of joy-filled life before (15:11) and a similar one in (10:10). Notice that when Jesus gives out something, it is a good thing and it is in large doses. He doesn’t skimp on the quantity or the quality.

John 15:11  I have told you this so that my joy may be in you and that your joy may be complete.

John 10:10  The thief comes only to steal and kill and destroy; I have come that they may have life, and have it to the full.

Joy in abundance is something that every Christian should have. It is a characteristic of the Kingdom of God and a fruit of the Holy Spirit Who resides within us (Rom 14:17, Gal 5:22, 1 Peter 1:8) and Jesus above all others should be the one to pray for His disciples to receive it because He was so aquainted with joy (Heb 1:9, 12:2).

Romans 14:17  For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit,

Galatians 5:22  But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness,

1 Peter 1:8  Though you have not seen him, you love him; and even though you do not see him now, you believe in him and are filled with an inexpressible and glorious joy,

Hebrews 1:9  You have loved righteousness and hated wickedness; therefore God, your God, has set you above your companions by anointing you with the oil of joy.”

Hebrews 12:2  Let us fix our eyes on Jesus, the author and perfecter of our faith, who for the joy set before him endured the cross, scorning its shame, and sat down at the right hand of the throne of God.

What would it be like to have the “full measure” of Jesus’ joy? How would it help you deal with the things you face in your life?

Why did Jesus pray for the disciples to receive the full measure of His joy now instead of waiting until He was with His Father? Because they were going to need it before His ascension.