The aide stands next to the sovereign
Ren is a heavenly stem, water among the five phases, the first of the three Kan trigram mountains, Zi at 0 degrees after it, Hai at 330 before it. A grave that sits Ren faces Bing at 165 degrees.
The name fits the position. Hai, just before Ren, carries Tianhuang, the Heavenly Sovereign, a noble star on a three auspicious mountain. Ren carries the aide. The school does not make a story of it. It is a reminder that 337.5 degrees separates a noble bearing from an ordinary one, and that a Ren range or peak is read on its own merits, not its neighbour's.
How an ordinary star earns its place
A range entering through Ren is walked before it is named: does it rise and fall, narrow before the head, does the head swell. If so, the school marks a Ren range under Tianfu and goes on to the cave. If not, the range fails on the ground and the star stays on the ring.
A peak on Ren seen from the cave is judged on shape: whole, upright and facing in, it is a sound sha, and Tianfu agrees. The same peak sagging on one side, or with a cut face, is a poor sha whatever the ring says. Water from Ren is read on its bend and its mouth. The Cui guan pian answers dragon, cave, sha and water with the ring, chapter by chapter, and an ordinary star in each stands behind the landform, not in front of it.
What this means on the ground
Tianfu sits on the Tianxing ring between Tianhuang on Hai and Tianlei on Zi. At a grave, stand behind the stone, sight along it, level the plate. Turn the line to each peak between north west and north and read the ring: 337.5 to 352.5 is Ren. Read three times. Close to 338 or 352 the peak is on a border: note the side it favours and check again a few steps along the stone.
At a house or shop, stand inside the door, back to it. A solid, settled building on the Ren bearing is a good sha. A gap between towers that funnels wind at the door, a sharp corner, or a road aimed at the entrance reads poorly, and Tianfu offers nothing against it.
Common mistakes
Reading the ring with a phone or a plain compass: the pairing of Tianfu to Ren lives on this school's luopan; other rings carry other names. Hearing helper in the name and expecting helpers: the school reads the name as imagery only. Counting Tianfu on the ring and skipping the walk: a Ren peak can hide a cut slope or a dump behind it. Measuring from a satellite map in true north: the needle reads magnetic north, and a few degrees moves a peak from Ren to Hai or Zi.
Questions people ask
What is the Tianfu star in feng shui?
The Tianxing star on the Ren mountain, 345 degrees north by north west. The name means Heaven's Aide, with the imagery of a helper or a right hand. An ordinary star that confirms a good Ren landform.
Is a house sitting Ren and facing Bing good?
Sitting Ren and facing Bing is close to the classic north south sitting, tilted a little west. Good or not depends on the ground: real support behind, open ground and gathered water in front. The star on the sitting mountain is read last.
What is the difference between Tianfu and Tianhuang?
They are neighbours. Tianhuang is on Hai at 330 degrees, a noble star on a three auspicious mountain. Tianfu is on Ren at 345 degrees and is ordinary. A range entering near 337.5 degrees is read several times before it gets either name.
If a range or peak sits on the Ren bearing at your site, have Master Zhang read it on the ring, or come to the Ganzhou field course and learn to read it yourself.