John Calvin Commentary Ephesians 2:18

"for through him we both have our access in one Spirit unto the Father." — Ephesians 2:18 (ASV)

For through him we both have access. This is an argument from the fact that we are permitted to draw near to God. But it may also be viewed as an announcement of peace; for wicked men, lulled into a profound sleep, sometimes deceive themselves with false notions of peace, but are never at rest, except when they have learned to forget the Divine judgment and to keep themselves at the greatest possible distance from God.

It was necessary, therefore, to explain the true nature of evangelical peace, which is widely different from a stupefied conscience, from false confidence, from proud boasting, or from ignorance of our own wretchedness. It is a settled composure, which leads us not to dread, but to desire and seek, the face of God.

Now, it is Christ who opens the door to us, indeed, who is himself the door (John 10:9). Since this is a double door, thrown open for the admission of both Jews and Gentiles, we are led to view God as exhibiting his fatherly kindness to both. He adds, by one Spirit; who leads and guides us to Christ, and by whom we cry, Abba, Father, (Romans 8:15) for from this arises the boldness of approach. Jews had various means of drawing near to God; now all have only one way: to be led by the Spirit of God.