Ephesians 2:18, "For through him we both have our access in one Spirit to the Father," is a powerful statement about the unity and relationship established between Jews and Gentiles through Christ. Let's break it down:

"For through him...": "Him" refers to Jesus Christ. The entire passage in Ephesians 2 is about how Christ has broken down the dividing wall between Jews and Gentiles.

"...we both...": "We both" refers to both Jews and Gentiles. Before Christ, Jews and Gentiles were separated by laws, traditions, and a sense of distinct identity.

"...have our access...": "Access" implies the ability to approach, enter into a relationship with, and be in the presence of. Before Christ, Gentiles did not have direct access to God in the same way that the Jews did who followed the law of Moses.

"...in one Spirit...": "One Spirit" refers to the Holy Spirit. The Holy Spirit is the agent through whom both Jews and Gentiles are brought into relationship with God. The unity is made possible through the unifying power of the Holy Spirit.

"...to the Father.": "The Father" refers to God. The ultimate goal is to be reconciled to God, to have a restored relationship with Him.

In summary, this verse means:

Through Jesus Christ, both Jews and Gentiles, who were once separated, now have equal access to God the Father. This access is granted and made possible by the Holy Spirit, who unites them as one body in Christ. It emphasizes the reconciliation and unity that Christ brings, allowing both groups to approach God directly and intimately.

Key Implications:

Inclusion: Gentiles are no longer excluded from God's presence.
Unity: Jews and Gentiles are united in Christ, breaking down ethnic and religious barriers.
Mediation: Jesus is the mediator through whom we can approach God.
The Trinity: It highlights the role of all three persons of the Trinity – Father, Son, and Holy Spirit – in our salvation and relationship with God.
Direct Relationship: Believers can have a personal and direct relationship with God.