diff --git a/homeassistant/components/template/alarm_control_panel.py b/homeassistant/components/template/alarm_control_panel.py
index 2ac91d39858..7c23fdcebcc 100644
--- a/homeassistant/components/template/alarm_control_panel.py
+++ b/homeassistant/components/template/alarm_control_panel.py
@@ -108,7 +108,7 @@ async def _async_create_entities(hass, config):
     alarm_control_panels = []
 
     for object_id, entity_config in config[CONF_ALARM_CONTROL_PANELS].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
         alarm_control_panels.append(
diff --git a/homeassistant/components/template/binary_sensor.py b/homeassistant/components/template/binary_sensor.py
index 68b3cd6d35a..187c7079f59 100644
--- a/homeassistant/components/template/binary_sensor.py
+++ b/homeassistant/components/template/binary_sensor.py
@@ -119,17 +119,21 @@ LEGACY_BINARY_SENSOR_SCHEMA = vol.All(
 )
 
 
-def rewrite_legacy_to_modern_conf(cfg: dict[str, dict]) -> list[dict]:
+def rewrite_legacy_to_modern_conf(
+    hass: HomeAssistant, cfg: dict[str, dict]
+) -> list[dict]:
     """Rewrite legacy binary sensor definitions to modern ones."""
     sensors = []
 
     for object_id, entity_cfg in cfg.items():
         entity_cfg = {**entity_cfg, CONF_OBJECT_ID: object_id}
 
-        entity_cfg = rewrite_common_legacy_to_modern_conf(entity_cfg, LEGACY_FIELDS)
+        entity_cfg = rewrite_common_legacy_to_modern_conf(
+            hass, entity_cfg, LEGACY_FIELDS
+        )
 
         if CONF_NAME not in entity_cfg:
-            entity_cfg[CONF_NAME] = template.Template(object_id)
+            entity_cfg[CONF_NAME] = template.Template(object_id, hass)
 
         sensors.append(entity_cfg)
 
@@ -183,7 +187,7 @@ async def async_setup_platform(
         _async_create_template_tracking_entities(
             async_add_entities,
             hass,
-            rewrite_legacy_to_modern_conf(config[CONF_SENSORS]),
+            rewrite_legacy_to_modern_conf(hass, config[CONF_SENSORS]),
             None,
         )
         return
diff --git a/homeassistant/components/template/config.py b/homeassistant/components/template/config.py
index 42a57cfc4aa..e2015743a0e 100644
--- a/homeassistant/components/template/config.py
+++ b/homeassistant/components/template/config.py
@@ -115,7 +115,7 @@ async def async_validate_config(hass: HomeAssistant, config: ConfigType) -> Conf
                 )
 
             definitions = list(cfg[new_key]) if new_key in cfg else []
-            definitions.extend(transform(cfg[old_key]))
+            definitions.extend(transform(hass, cfg[old_key]))
             cfg = {**cfg, new_key: definitions}
 
         config_sections.append(cfg)
diff --git a/homeassistant/components/template/cover.py b/homeassistant/components/template/cover.py
index d50067f6278..2c84387ed64 100644
--- a/homeassistant/components/template/cover.py
+++ b/homeassistant/components/template/cover.py
@@ -106,7 +106,7 @@ async def _async_create_entities(hass, config):
     covers = []
 
     for object_id, entity_config in config[CONF_COVERS].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
 
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
diff --git a/homeassistant/components/template/fan.py b/homeassistant/components/template/fan.py
index 20a2159e378..cedd7d0d725 100644
--- a/homeassistant/components/template/fan.py
+++ b/homeassistant/components/template/fan.py
@@ -94,7 +94,7 @@ async def _async_create_entities(hass, config):
     fans = []
 
     for object_id, entity_config in config[CONF_FANS].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
 
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
diff --git a/homeassistant/components/template/light.py b/homeassistant/components/template/light.py
index ba6b8ce846b..cae6c0cebc1 100644
--- a/homeassistant/components/template/light.py
+++ b/homeassistant/components/template/light.py
@@ -126,7 +126,7 @@ async def _async_create_entities(hass, config):
     lights = []
 
     for object_id, entity_config in config[CONF_LIGHTS].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
         lights.append(
diff --git a/homeassistant/components/template/lock.py b/homeassistant/components/template/lock.py
index 0fa219fcd9b..5c0b67a23dc 100644
--- a/homeassistant/components/template/lock.py
+++ b/homeassistant/components/template/lock.py
@@ -59,7 +59,7 @@ PLATFORM_SCHEMA = LOCK_PLATFORM_SCHEMA.extend(
 
 async def _async_create_entities(hass, config):
     """Create the Template lock."""
-    config = rewrite_common_legacy_to_modern_conf(config)
+    config = rewrite_common_legacy_to_modern_conf(hass, config)
     return [TemplateLock(hass, config, config.get(CONF_UNIQUE_ID))]
 
 
diff --git a/homeassistant/components/template/sensor.py b/homeassistant/components/template/sensor.py
index 70a2d5dd650..ee24407699d 100644
--- a/homeassistant/components/template/sensor.py
+++ b/homeassistant/components/template/sensor.py
@@ -142,17 +142,21 @@ def extra_validation_checks(val):
     return val
 
 
-def rewrite_legacy_to_modern_conf(cfg: dict[str, dict]) -> list[dict]:
+def rewrite_legacy_to_modern_conf(
+    hass: HomeAssistant, cfg: dict[str, dict]
+) -> list[dict]:
     """Rewrite legacy sensor definitions to modern ones."""
     sensors = []
 
     for object_id, entity_cfg in cfg.items():
         entity_cfg = {**entity_cfg, CONF_OBJECT_ID: object_id}
 
-        entity_cfg = rewrite_common_legacy_to_modern_conf(entity_cfg, LEGACY_FIELDS)
+        entity_cfg = rewrite_common_legacy_to_modern_conf(
+            hass, entity_cfg, LEGACY_FIELDS
+        )
 
         if CONF_NAME not in entity_cfg:
-            entity_cfg[CONF_NAME] = template.Template(object_id)
+            entity_cfg[CONF_NAME] = template.Template(object_id, hass)
 
         sensors.append(entity_cfg)
 
@@ -210,7 +214,7 @@ async def async_setup_platform(
         _async_create_template_tracking_entities(
             async_add_entities,
             hass,
-            rewrite_legacy_to_modern_conf(config[CONF_SENSORS]),
+            rewrite_legacy_to_modern_conf(hass, config[CONF_SENSORS]),
             None,
         )
         return
diff --git a/homeassistant/components/template/switch.py b/homeassistant/components/template/switch.py
index fbb35399ef8..9145625f706 100644
--- a/homeassistant/components/template/switch.py
+++ b/homeassistant/components/template/switch.py
@@ -76,7 +76,7 @@ async def _async_create_entities(hass, config):
     switches = []
 
     for object_id, entity_config in config[CONF_SWITCHES].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
         switches.append(
diff --git a/homeassistant/components/template/template_entity.py b/homeassistant/components/template/template_entity.py
index b5d2ab6fff3..a074f828284 100644
--- a/homeassistant/components/template/template_entity.py
+++ b/homeassistant/components/template/template_entity.py
@@ -123,7 +123,9 @@ LEGACY_FIELDS = {
 
 
 def rewrite_common_legacy_to_modern_conf(
-    entity_cfg: dict[str, Any], extra_legacy_fields: dict[str, str] | None = None
+    hass: HomeAssistant,
+    entity_cfg: dict[str, Any],
+    extra_legacy_fields: dict[str, str] | None = None,
 ) -> dict[str, Any]:
     """Rewrite legacy config."""
     entity_cfg = {**entity_cfg}
@@ -138,11 +140,11 @@ def rewrite_common_legacy_to_modern_conf(
 
         val = entity_cfg.pop(from_key)
         if isinstance(val, str):
-            val = Template(val)
+            val = Template(val, hass)
         entity_cfg[to_key] = val
 
     if CONF_NAME in entity_cfg and isinstance(entity_cfg[CONF_NAME], str):
-        entity_cfg[CONF_NAME] = Template(entity_cfg[CONF_NAME])
+        entity_cfg[CONF_NAME] = Template(entity_cfg[CONF_NAME], hass)
 
     return entity_cfg
 
@@ -310,7 +312,6 @@ class TemplateEntity(Entity):
         # Try to render the name as it can influence the entity ID
         self._attr_name = fallback_name
         if self._friendly_name_template:
-            self._friendly_name_template.hass = hass
             with contextlib.suppress(TemplateError):
                 self._attr_name = self._friendly_name_template.async_render(
                     variables=variables, parse_result=False
@@ -319,14 +320,12 @@ class TemplateEntity(Entity):
         # Templates will not render while the entity is unavailable, try to render the
         # icon and picture templates.
         if self._entity_picture_template:
-            self._entity_picture_template.hass = hass
             with contextlib.suppress(TemplateError):
                 self._attr_entity_picture = self._entity_picture_template.async_render(
                     variables=variables, parse_result=False
                 )
 
         if self._icon_template:
-            self._icon_template.hass = hass
             with contextlib.suppress(TemplateError):
                 self._attr_icon = self._icon_template.async_render(
                     variables=variables, parse_result=False
@@ -388,8 +387,10 @@ class TemplateEntity(Entity):
             If True, the attribute will be set to None if the template errors.
 
         """
-        assert self.hass is not None, "hass cannot be None"
-        template.hass = self.hass
+        if self.hass is None:
+            raise ValueError("hass cannot be None")
+        if template.hass is None:
+            raise ValueError("template.hass cannot be None")
         template_attribute = _TemplateAttribute(
             self, attribute, template, validator, on_update, none_on_template_error
         )
diff --git a/homeassistant/components/template/trigger.py b/homeassistant/components/template/trigger.py
index 09ad0754634..44ac2d93051 100644
--- a/homeassistant/components/template/trigger.py
+++ b/homeassistant/components/template/trigger.py
@@ -49,9 +49,7 @@ async def async_attach_trigger(
     """Listen for state changes based on configuration."""
     trigger_data = trigger_info["trigger_data"]
     value_template: Template = config[CONF_VALUE_TEMPLATE]
-    value_template.hass = hass
     time_delta = config.get(CONF_FOR)
-    template.attach(hass, time_delta)
     delay_cancel = None
     job = HassJob(action)
     armed = False
diff --git a/homeassistant/components/template/vacuum.py b/homeassistant/components/template/vacuum.py
index e512ce2eb04..1d021bcb571 100644
--- a/homeassistant/components/template/vacuum.py
+++ b/homeassistant/components/template/vacuum.py
@@ -100,7 +100,7 @@ async def _async_create_entities(hass, config):
     vacuums = []
 
     for object_id, entity_config in config[CONF_VACUUMS].items():
-        entity_config = rewrite_common_legacy_to_modern_conf(entity_config)
+        entity_config = rewrite_common_legacy_to_modern_conf(hass, entity_config)
         unique_id = entity_config.get(CONF_UNIQUE_ID)
 
         vacuums.append(
diff --git a/homeassistant/components/template/weather.py b/homeassistant/components/template/weather.py
index 5c3e4107b2c..ec6d1f08dd3 100644
--- a/homeassistant/components/template/weather.py
+++ b/homeassistant/components/template/weather.py
@@ -153,7 +153,7 @@ async def async_setup_platform(
         )
         return
 
-    config = rewrite_common_legacy_to_modern_conf(config)
+    config = rewrite_common_legacy_to_modern_conf(hass, config)
     unique_id = config.get(CONF_UNIQUE_ID)
 
     async_add_entities(
diff --git a/tests/components/template/test_alarm_control_panel.py b/tests/components/template/test_alarm_control_panel.py
index 6a2a95a64eb..ea63d7b9926 100644
--- a/tests/components/template/test_alarm_control_panel.py
+++ b/tests/components/template/test_alarm_control_panel.py
@@ -244,7 +244,7 @@ async def test_template_syntax_error(
                 "platform": "template",
                 "panels": {
                     "test_template_panel": {
-                        "name": "Template Alarm Panel",
+                        "name": '{{ "Template Alarm Panel" }}',
                         "value_template": "disarmed",
                         **OPTIMISTIC_TEMPLATE_ALARM_CONFIG,
                     }
diff --git a/tests/components/template/test_template_entity.py b/tests/components/template/test_template_entity.py
index dcceea95181..c09a09750fe 100644
--- a/tests/components/template/test_template_entity.py
+++ b/tests/components/template/test_template_entity.py
@@ -11,14 +11,14 @@ async def test_template_entity_requires_hass_set(hass: HomeAssistant) -> None:
     """Test template entity requires hass to be set before accepting templates."""
     entity = template_entity.TemplateEntity(hass)
 
-    with pytest.raises(AssertionError):
+    with pytest.raises(ValueError, match="^hass cannot be None"):
         entity.add_template_attribute("_hello", template.Template("Hello"))
 
     entity.hass = object()
-    entity.add_template_attribute("_hello", template.Template("Hello", None))
+    with pytest.raises(ValueError, match="^template.hass cannot be None"):
+        entity.add_template_attribute("_hello", template.Template("Hello", None))
 
     tpl_with_hass = template.Template("Hello", entity.hass)
     entity.add_template_attribute("_hello", tpl_with_hass)
 
-    # Because hass is set in `add_template_attribute`, both templates match `tpl_with_hass`
-    assert len(entity._template_attrs.get(tpl_with_hass, [])) == 2
+    assert len(entity._template_attrs.get(tpl_with_hass, [])) == 1