That’s one of God’s prescriptions for a strong, faithful marriage.
Of course, hinging your marriage on the gospel of His Son is His main prescription, but physical and sexual intimacy definitely matter to Him.
Proverbs 5-7 almost function as a unit, warning us to avoid adulterous people, by prescribing, among other things, great sexual intimacy with our own spouses.
Since marriage is a symbol of Christ’s relationship with His Church, in the same way, if you want to be much more faithful to God, then be a lot more intimate with Him.
Relevant parts of Proverbs 5-7 in context:
Warning Against Adultery
5 My son, pay attention to my wisdom,
turn your ear to my words of insight,
2 that you may maintain discretion
and your lips may preserve knowledge.
3 For the lips of the adulterous woman drip honey,
and her speech is smoother than oil;
4 but in the end she is bitter as gall,
sharp as a double-edged sword.
5 Her feet go down to death;
her steps lead straight to the grave.
6 She gives no thought to the way of life;
her paths wander aimlessly, but she does not know it.
7 Now then, my sons, listen to me;
do not turn aside from what I say.
8 Keep to a path far from her,
do not go near the door of her house,
9 lest you lose your honor to others
and your dignity[a] to one who is cruel,
10 lest strangers feast on your wealth
and your toil enrich the house of another.
11 At the end of your life you will groan,
when your flesh and body are spent.
12 You will say, “How I hated discipline!
How my heart spurned correction!
13 I would not obey my teachers
or turn my ear to my instructors.
14 And I was soon in serious trouble
in the assembly of God’s people.”
15 Drink water from your own cistern,
running water from your own well.
16 Should your springs overflow in the streets,
your streams of water in the public squares?
17 Let them be yours alone,
never to be shared with strangers.
18 May your fountain be blessed,
and may you rejoice in the wife of your youth.
19 A loving doe, a graceful deer—
may her breasts [drench] you always,
may you ever be intoxicated with her love.
20 Why, my son, be intoxicated with another man’s wife?
Why embrace the bosom of a wayward woman?
21 For your ways are in full view of the Lord,
and he examines all your paths.
22 The evil deeds of the wicked ensnare them;
the cords of their sins hold them fast.
23 For lack of discipline they will die,
led astray by their own great folly.
- Proverbs 5:9 Or years
Warning Against Adultery
20 My son, keep your father’s command
and do not forsake your mother’s teaching.
21 Bind them always on your heart;
fasten them around your neck.
22 When you walk, they will guide you;
when you sleep, they will watch over you;
when you awake, they will speak to you.
23 For this command is a lamp,
this teaching is a light,
and correction and instruction
are the way to life,
24 keeping you from your neighbor’s wife,
from the smooth talk of a wayward woman.
25 Do not lust in your heart after her beauty
or let her captivate you with her eyes.
26 For a prostitute can be had for a loaf of bread,
but another man’s wife preys on your very life.
27 Can a man scoop fire into his lap
without his clothes being burned?
28 Can a man walk on hot coals
without his feet being scorched?
29 So is he who sleeps with another man’s wife;
no one who touches her will go unpunished.
30 People do not despise a thief if he steals
to satisfy his hunger when he is starving.
31 Yet if he is caught, he must pay sevenfold,
though it costs him all the wealth of his house.
32 But a man who commits adultery has no sense;
whoever does so destroys himself.
33 Blows and disgrace are his lot,
and his shame will never be wiped away.
34 For jealousy arouses a husband’s fury,
and he will show no mercy when he takes revenge.
35 He will not accept any compensation;
he will refuse a bribe, however great it is.
Warning Against the Adulterous Woman
7 My son, keep my words
and store up my commands within you.
2 Keep my commands and you will live;
guard my teachings as the apple of your eye.
3 Bind them on your fingers;
write them on the tablet of your heart.
4 Say to wisdom, “You are my sister,”
and to insight, “You are my relative.”
5 They will keep you from the adulterous woman,
from the wayward woman with her seductive words.
6 At the window of my house
I looked down through the lattice.
7 I saw among the simple,
I noticed among the young men,
a youth who had no sense.
8 He was going down the street near her corner,
walking along in the direction of her house
9 at twilight, as the day was fading,
as the dark of night set in.
10 Then out came a woman to meet him,
dressed like a prostitute and with crafty intent.
11 (She is unruly and defiant,
her feet never stay at home;
12 now in the street, now in the squares,
at every corner she lurks.)
13 She took hold of him and kissed him
and with a brazen face she said:
14 “Today I fulfilled my vows,
and I have food from my fellowship offering at home.
15 So I came out to meet you;
I looked for you and have found you!
16 I have covered my bed
with colored linens from Egypt.
17 I have perfumed my bed
with myrrh, aloes and cinnamon.
18 Come, let’s drink deeply of love till morning;
let’s enjoy ourselves with love!
19 My husband is not at home;
he has gone on a long journey.
20 He took his purse filled with money
and will not be home till full moon.”
21 With persuasive words she led him astray;
she seduced him with her smooth talk.
22 All at once he followed her
like an ox going to the slaughter,
like a deer[a] stepping into a noose[b]
23 till an arrow pierces his liver,
like a bird darting into a snare,
little knowing it will cost him his life.
24 Now then, my sons, listen to me;
pay attention to what I say.
25 Do not let your heart turn to her ways
or stray into her paths.
26 Many are the victims she has brought down;
her slain are a mighty throng.
27 Her house is a highway to the grave,
leading down to the chambers of death.