God Served by Supplications

The worship that God requires of us is not so focused on the glory of God that it is oblivious to our need, because our need is for him, and God having created us for himself is glorified in our turning to him in time of need. He is glorified when he is praised as our help and saviour. The glory of God is open to human need. God is served by our supplications because God is philanthropos (philanthropic), to use that favorite phrase of the Greek liturgy. God is served by our supplications for his blessing because it is his will to bless us.
Hughes Oliphant Old "Calvin's Theology of Worship" (from 'Give Praise to God')

The Difficulty with God-Centered Worship

“There is one major difficulty with God-centered worship. God is dangerous, and thus is not altogether safe to come into His presence. Just ask Moses. Or Nadab and Abihu. Or Uzzah. Or Isaiah. Or Job. Or Ananias and Sapphira. All of these people had close encounters with the God of glory. In some cases they were utterly destroyed by the terror of His majesty. In other cases they were simply undone by the brightness of His glory. But in every case they discovered that it is not completely safe to worship a God who is glorious in His holiness. It is for this reason that we give praise to God in Jesus’ name. Our worship must be Christ-honoring. … God’s name is never simply a title, but it always represents the full majesty of His being and attributes. The name of Jesus refers specifically to His person and work as the Savior of sinners. It is the name of salvation. … It is only on the basis of Christ’s atoning work that anyone can ever approach God. Before we approach God in worship, we must be reconciled to Him through Christ and His cross.” – Philip Graham Ryken ‘City on a Hill’ p.68-70