The second glorious nugget here is 'pray in the Holy Spirit'. 'Pray' here is present middle, the present indicating 'continually pray'. 'In the Holy Spirit' can mean 'by', 'with', 'in the sphere of', 'as led by', 'in the power of' and more. It should be taken in a global way. Pray as led by, in accordance with, by the urging of, in the love of etc etc, the Spirit. It is prayer drenched in the Spirit's grace, love, guidance and urging. It recalls Paul's injunction in Eph 6:18: 'pray in the Spirit on all occasions with all kinds of prayers and requests.'
Prayer is the basic humanward side of response to God. Worship is essentially prayer. Prayer involves lots of listening, and sharing with God one's deepest thoughts, concerns, desires and yearnings. It should characterise us as Christians. It is one of the means of 'building ourselves up in the most holy faith'.
There are two equal and opposite extremes. We can become fatalistic and extreme and believe prayer is pointless because God is sovereign and do what God wants to do despite us; that is, our prayers are really meaningless because God is God. God has promised to honour prayer, he has told us that our prayers can make a difference, he will move in response to them. On the other hand we can believe that God does nothing without our prayers and it is our prayers that are the power that changes the world. Our prayers are powerful but only in that God moves. God is what changes the world, we pray, we trust, God moves.
So how is your prayer life? Mine is not great at the moment. It is sure time to sort it out! Better go and pray then, bye!