In this passage of Romans (Chapter 8:18-30), is the discussion about the participation of Christians in the midst of everyday suffering that is also experienced by the rest of all creation. It's in this discussion, and in our verse today, that we see the difference between our future and present as Christians. We know that our future is Christ, as God's children (John 1:12 - Verse of the Day article) and heirs of His kingdom (Romans 8:17), is everything that we long for. At our present, however, this hasn't yet come - so therefore we continue to suffer alongside the rest of creation, groaning for the life that is to come to those who believe.
So, how do we live in the meantime?
The answer has a lot to do with the Holy Spirit. As believers, we receive the Holy Spirit (as it is given to us) when we come to faith in Christ. A way to think about this is like God has given believers His own Spirit as a deposit or down payment on the future that we're longing for (Ephesians 1:13-14; 2 Corinthians 1:22).
It is through the Spirit that God provides for us while here in this life. Even as Christians, we remain weak in and of ourselves and therefore we need God's strength through the Spirit. We have baffling emotions, fragile bodies, and can become weak in our faith and resistance to temptation. Every single day we fail. It is the Holy Spirit that makes all the difference for us - as we desire to draw near to God, grow in our understanding, and be like Christ that our desires, morals, and thoughts align with His will (John 15:7 - Verse of the Day article). I want to reiterate that it is because of the Holy Spirit that we're able to do this. Therefore, it is the Holy Spirit that makes all the difference. It is the Holy Spirit that continually and consistently helps us even through our weakness. It is the Holy Spirit that steps in. It is the Holy Spirit that helps lift the burden.
Further, Paul tells us that we are so weak that at times we aren't even able to know what to pray for. We feel the longing and need to pray, to speak to our Father God - but what do we ask for? This is when, as we're told in this verse, that the Holy Spirit steps in and carries these unsaid prayers - the thoughts and feelings that we can't express to God.
It is the Holy Spirit that creates both the connection from ourselves to God and then provides the content of our communication with the Father.