Sin-sa (辛巳) Day Pillar: Yin Metal Snake and the Hidden Combination

Sin-sa (辛巳, 신사) is the day pillar (일주 日柱, ilju) with Sin 辛, the Yin Metal Day Master, above Sa 巳, the Snake. It is number 18 of the sixty-pillar cycle (육십갑자 六十甲子, yuksip-gapja). Think of a jeweller holding a silver ring over a flame to fit a setting. The heat is controlled and the result is made for display. Sin-sa is fine metal shaped by careful fire.

The image

Fire controls Metal, so the branch acts on the stem as its Officer: the star of rules, standing and accountability. The hidden stems (지장간 支藏干, jijanggan) of Sa are Mu 戊 Yang Earth for 7 days, Gyeong 庚 Yang Metal for 7 days and Byeong 丙 Yang Fire for 16 days.

Byeong (丙), the main hidden stem, is Sin's Direct Officer. It also has a special relationship with the stem: 丙 and 辛 form one of the five stem combinations. So Sin-sa's Day Master is bound, inside its own pillar, to the very star that governs it. Classical readers call such a pillar loyal and committed to whatever it serves, and some note that a combined Day Master can be slow to act for itself.

The other two hidden stems soften the picture. Mu (戊) is Direct Resource, Earth that turns Fire's pressure into support. Gyeong (庚) is Rob Wealth, a stronger sibling metal; the Snake is where Gyeong begins its life cycle, which is why Metal is said to be "born" in this Fire branch.

On the twelve life stages (십이운성 十二運星, sibi-unseong), Sin on Sa is at Death (사 死, sa), under the reversed sequence most Korean schools use for Yin stems. The minority that runs Yin stems on the Yang sequence would place Sin differently, and some readers prefer to judge strength from hidden stems alone. Either way, the Day Master leans on the hidden Earth and Metal here.

The Void (공망 空亡, gongmang) branches are the Monkey (申) and the Rooster (酉).

Character

Sin-sa people are often poised, careful about appearances and conscious of how they are seen. The combination with the Officer gives a strong sense of obligation: once they accept a role, they take it seriously and work to its standard. They tend to be polite, well-prepared and good at reading what an institution expects.

Their strengths are reliability, polish and a talent for refining things others have started. The blind spots are anxiety about status, difficulty saying no to people above them, and a habit of hiding strain behind good manners. Snake energy adds an observant, private streak: Sin-sa usually knows more than it says.

Relationships

The spouse palace (배우자궁 配偶者宮, baeujagung) holds Direct Officer, and the stem combines with it. For women's charts, traditional texts read this as the husband star in its own palace and bound to the self, a classic picture of commitment. For anyone, Sin-sa tends to take partnership formally and loyally, and prefers a partner with clear standing or principles. The caution is losing oneself in the relationship, or staying in one out of duty after it has stopped working.

Traditional pairings: the heaven-and-earth combination (천지합 天地合, cheonjihap) is Byeong-sin (丙申), with 丙 combining 辛 and 申 combining 巳. The "heaven strikes, earth clashes" partner (천극지충 天剋地沖, cheongeuk-jichung) is Jeong-hae (丁亥). Both are classical patterns rather than predictions.

Work and money

Sin-sa favours institutions with clear ladders: government, diplomacy, corporate management, compliance, academic administration, hospitality at the high end, brand stewardship, and professions with licences. The Officer combination suggests someone who grows into a title and represents it well.

Money tends to come from position and steady pay. There is no Wealth star in the branch, so trading and speculation are less natural. The Rob Wealth inside the Snake is a reminder to watch money lent to colleagues and siblings.

How Sin-sa differs from the other Sin pillars

• Sin-hae (辛亥) is its clash partner by branch. Sin-hae has a Hurting Officer branch that questions authority; Sin-sa has the Direct Officer that embodies it.
• Sin-mi (辛未) faces hidden Seven Killings but leans on Indirect Resource, so it serves through care and study rather than rank.
• Sin-myo (辛卯) looks to markets and trade, while Sin-sa looks to institutions.
• Sin-yu (辛酉) stands at Officialdom and answers to itself; Sin-sa answers to its role.

Sin-sa in 2026–2030

• 2026, Byeong-o (丙午): Direct Officer over Seven Killings, and Byeong forms a stem combination (合) with your Sin. With Officer already bound to the stem, the year amplifies duty, offers of position, and formal commitments.
• 2027, Jeong-mi (丁未): Seven Killings over Indirect Resource; a demanding year, eased by learning.
• 2028, Mu-sin (戊申): Direct Resource over Rob Wealth, and the Monkey forms a branch harmony (六合) with the Snake in the spouse palace, often read as goodwill in close relationships.
• 2029, Gi-yu (己酉): Indirect Resource over Friend; Metal gains support and company.
• 2030, Gyeong-sul (庚戌): Rob Wealth over Direct Resource; good backing with some competition.

FAQ

Why does Sin-sa have a "hidden combination"?

The Snake's main hidden stem is Byeong, which forms a stem combination with Sin. Traditional readers see the Day Master as bound to its own Direct Officer, which points to loyalty and a strong sense of duty.

Does the Death stage mean anything bad for Sin-sa?

No. Death is one of the twelve life stages and describes where a stem's own energy is low on a branch. Schools also differ on how Yin stems move through the cycle.

How do I check whether I was born on a Sin-sa day?

Use the free day pillar calculator with your birth date and time.

Hidden stems in the branch

The Snake branch carries these stems inside it (지장간). Read from the Sin Day Master, each takes a Ten God role.

Sin-sa and the years 2026–2030

Each year has its own pillar. Its stem and branch take Ten God roles for this Day Master, and its branch may combine or clash with your day branch.

Combining and clashing pillars

Other Sin (辛) day pillars

Other day pillars on the Snake