Read Romans 8:26-30
Paul now moves onto a new outcome from having the Spirit. The Spirit sustains us in our suffering (v24-25), and now it sustains us in our weakness. This weakness being referred to is the limitation of the human condition. We are all weak and we all need to be sustained by the Spirit. Because of this weakness, we don't even know what to pray for! However, the Spirit comes to our rescue. Jesus is in heaven interceding for us, and the Spirit is with us also interceding for us. We need this because we don't know what God's plan for us is, His will is a mystery to us without the Spirit. But the Spirit, the Spirit is God, knows the will of God and prays for us perfectly in tune with God's will. This is why we must live by the Spirit.
Verse 34 tells us that Jesus intercedes for us before the Father guaranteeing our salvation. Here in verse 27, the Spirit is interceding for us - in our hearts, preparing us for that salvation, the hope we have (verses 24-25).
Verse 28 is just so famous:
And we know that in all things God works for the good of those who love him, who have been called according to his purpose. (Romans 8:28)
This speaks of God's 'providence', this is God's intervention in the universe! His sovereignty. Everything is under His rule, His Kingship! God's rule over all the events of life.
'All things' are the focus here, (our situation, our life, everything that happens). However, the glory for this is God's. It is through His Spirit that 'all things' work for our good. We can not boast or take praise. The praise is for Him alone!
Good. In line with His will and His plan. Moving towards the glory to come - the final glory! A benefit of being a child of God in this life.
For who? For those who love God. God's people. This does not imply "love Him more to get more", rather it is an outcome of God's love for us under His sovereign rule.
And those he predestined, he also called; those he called, he also justified; those he justified, he also glorified. (Romans 8:30)
When we come into a relationship with God we are being conformed to the image of Jesus Christ. We are on a road, experiencing a journey towards a goal - the goal - of the final glorification. We are brought into God's own people - through Justification - being declared innocent before God. Lots and lots of themes connected with Soteriology - the doctrine of salvation here, including election, predestination, and eternal security, but the main point is that God has a plan for each one of us, leading to our future glory. Verse 28 points to our assurance for the present life, while verses 29-30 point to our future glorification with Christ!