Christ had just said (v. 9), "Ask, and it shall be given": God's giving is inseparably connected with our asking. He applies this especially to the Holy Spirit. As surely as a father on earth gives bread to his child, so God gives the Holy Spirit to them that ask Him. The whole ministration of the Spirit is ruled by the one great law: God must give, we must ask. When the Holy Spirit was poured out at Pentecost with a flow that never ceases, it was in answer to prayer. The inflow into the believer's heart, and His outflow in the rivers of living water, ever still depend upon the law: "Ask, and it shall be given." In connection with our confession of the lack of prayer, we have said that what we need is some due apprehension of the place it occupies in God's plan of redemption; we shall perhaps nowhere see this more clearly than in the first half of the Acts of the Apostles. The story of the birth of the Church in the outpouring of the Holy Spirit, and of the first freshness of its heavenly life in the power of that Spirit, will teach us how _prayer on earth_, whether as cause or effect, _is the true measure of the presence of the Spirit of heaven_. We begin with the well-known words (i. 13), "These all continued with one accord in prayer and supplication." And then there follows: "And when the day of Pentecost was fully come, they were all with one accord in one place. And they were all filled with the Holy Ghost. And the same day there were added to them about three thousand souls." The great work of redemption had been accomplished. The Holy Spirit had been promised by Christ "not many days hence." He had sat down on His throne and received the Spirit from the Father. But all this was not enough. One thing more was needed: the ten days' united continued supplication of the disciples. It was intense, continued prayer that prepared the disciples' hearts, that opened the windows of heaven, that brought down the promised gift. As little as the power of the Spirit could be given without Christ sitting on the throne, _could it descend without the disciples on the footstool of the throne_. For all the ages the law is laid down here, at the birth of the Church, that whatever else may be found on earth, the power of the Spirit must be prayed down from heaven. The measure of believing, continued prayer will be the measure of the Spirit's working in the Church. Direct, definite, determined prayer is what we need.