Straight out of v.30 and his commands for Christian households Paul says:
“For this reason a man will leave his father and mother and will be joined to his wife, and the two will become one flesh. This mystery is great—but I am actually speaking with reference to Christ and the church. Nevertheless, each one of you must also love his own wife as he loves himself, and the wife must respect her husband.”
(Ephesians 5.31-33, NET)
Quoting from Genesis 2.24 Paul underscores his exhortations about Christian households with a profound theological point: marriage is an earthly preview of the church in eternity (v.32, cf. Revelation 20.4, 21.1-4).
Marriage, then, in addition to being a God-ordained, love-filled union here on earth actually shows us what life will be like in heaven. Not so much that we will marry or be given in marriage (Matthew 22.30) but more the loving, leading, and yielding relationship of husband and wife.
For those who are unmarried or not yet married, for those who don’t know if they will ever marry, marriage is not prescribed for all believers (1 Corinthians 7.25-28) and is certainly not salvific. Whether we are married or not we can appreciate the earthly example of an eternal truth: those who turn to Jesus in repentance and faith will forever be cared for, loved, and provided for by the One who gave Himself for their sins at the cross.