Marriage is a picture of self denying love as shown by Jesus on the cross

Wives, submit to your own husbands, as to the Lord.
23 For the husband is head of the wife, as also Christ is head of the church; and He is the Savior of the body.
24 Therefore, just as the church is subject to Christ, so let the wives be to their own husbands in everything.
25 ¶ Husbands, love your wives, just as Christ also loved the church and gave Himself for her,
26 that He might sanctify and cleanse her with the washing of water by the word,
27 that He might present her to Himself a glorious church, not having spot or wrinkle or any such thing, but that she should be holy and without blemish.
28 So husbands ought to love their own wives as their own bodies; he who loves his wife loves himself.
29 For no one ever hated his own flesh, but nourishes and cherishes it, just as the Lord does the church.
30 For we are members of His body,fn of His flesh and of His bones.
31 “For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh.”fn
32 This is a great mystery, but I speak concerning Christ and the church.
33 Nevertheless let each one of you in particular so love his own wife as himself, and let the wife see that she respects her husband.