diff --git a/doc/fixes35.0 b/doc/fixes35.0
index 15d49459c..f2a1c41b1 100644
--- a/doc/fixes35.0
+++ b/doc/fixes35.0
@@ -83,6 +83,7 @@ dipping in acid can erode the dipped object
 various actions--such as enchanting--performed on an unpaid shop object
 	either force the hero to buy the item (when its value is lowered) or
 	increase the current bill (when its value is raised)
+adjust health threshold where wounded hero will be healed by successful prayer
 
 
 Platform- and/or Interface-Specific Fixes
diff --git a/include/extern.h b/include/extern.h
index bed2f8e60..6623fdf60 100644
--- a/include/extern.h
+++ b/include/extern.h
@@ -1636,6 +1636,7 @@ E const char *NDECL(bottlename);
 
 /* ### pray.c ### */
 
+E boolean FDECL(critically_low_hp, (BOOLEAN_P));
 #ifdef USE_TRAMPOLI
 E int NDECL(prayer_done);
 #endif
diff --git a/src/pray.c b/src/pray.c
index 26b83c3db..3c5afb1a8 100644
--- a/src/pray.c
+++ b/src/pray.c
@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)pray.c	3.5	2005/06/21	*/
+/*	SCCS Id: @(#)pray.c	3.5	2005/06/24	*/
 /* Copyright (c) Benson I. Margulies, Mike Stephenson, Steve Linhart, 1989. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -116,6 +116,34 @@ but that's really hard.
 #define on_shrine()	((levl[u.ux][u.uy].altarmask & AM_SHRINE) != 0)
 #define a_align(x,y)	((aligntyp)Amask2align(levl[x][y].altarmask & AM_MASK))
 
+/* criticially low hit points if hp <= 5 or hp <= maxhp/N for some N */
+boolean
+critically_low_hp(only_if_injured)
+boolean only_if_injured;	/* determines whether maxhp <= 5 matters */
+{
+    int divisor, hplim,
+	curhp = Upolyd ? u.mh : u.uhp,
+	maxhp = Upolyd ? u.mhmax : u.uhpmax;
+
+    if (only_if_injured && !(curhp < maxhp)) return FALSE;
+    /* if maxhp is extremely high, use lower threshold for the division test
+       (golden glow cuts off at 11+5*lvl, nurse interaction at 25*lvl; this
+       ought to use monster hit dice--and a smaller multiplier--rather than
+       ulevel when polymorphed, but polyself doesn't maintain that) */
+    hplim = 15 * u.ulevel;
+    if (maxhp > hplim) maxhp = hplim;
+    /* 7 used to be the unconditional divisor */
+    switch (xlev_to_rank(u.ulevel)) {	/* maps 1..30 into 0..8 */
+    case 0: case 1: divisor = 5; break;	/* explvl 1 to 5 */
+    case 2: case 3: divisor = 6; break;	/* explvl 6 to 13 */
+    case 4: case 5: divisor = 7; break;	/* explvl 14 to 21 */
+    case 6: case 7: divisor = 8; break;	/* explvl 22 to 29 */
+    default:	    divisor = 9; break;	/* explvl 30+ */
+    }
+    /* 5 is a magic number in TROUBLE_HIT handling below */
+    return (curhp <= 5 || curhp * divisor <= maxhp);
+}
+
 STATIC_OVL int
 in_trouble()
 {
@@ -141,8 +169,7 @@ in_trouble()
 	if(u.utrap && u.utraptype == TT_LAVA) return(TROUBLE_LAVA);
 	if(Sick) return(TROUBLE_SICK);
 	if(u.uhs >= WEAK) return(TROUBLE_STARVING);
-	if (Upolyd ? (u.mh <= 5 || u.mh*7 <= u.mhmax) :
-		(u.uhp <= 5 || u.uhp*7 <= u.uhpmax)) return TROUBLE_HIT;
+	if (critically_low_hp(FALSE)) return TROUBLE_HIT;
 	if(u.ulycn >= LOW_PM) return(TROUBLE_LYCANTHROPE);
 	if(near_capacity() >= EXT_ENCUMBER && AMAX(A_STR)-ABASE(A_STR) > 3)
 		return(TROUBLE_COLLAPSING);