Matthew Henry on Romans 8:26-27

Though the infirmities of Christians are many and great, so that they would be overpowered if left to themselves, yet the Holy Spirit supports them. The Spirit, as an enlightening Spirit, teaches us what to pray for; as a sanctifying Spirit, works and stirs up praying graces; as a comforting Spirit, silences our fears, and helps us over all discouragements. The Holy Spirit is the spring of all desires toward God, which are often more than words can utter. The Spirit who searches the hearts, can perceive the mind and will of the spirit, the renewed mind, and advocates his cause. The Spirit makes intercession to God, and the enemy prevails not.