diff --git a/lib/schemaType.js b/lib/schemaType.js
index e3caa4ff03..74d713795d 100644
--- a/lib/schemaType.js
+++ b/lib/schemaType.js
@@ -803,6 +803,21 @@ SchemaType.prototype.get = function(fn) {
   return this;
 };
 
+/**
+ * Adds multiple validators for this document path.
+ * Calls `validate()` for every element in validators.
+ *
+ * @param {Array<RegExp|Function|Object>} validators
+ * @returns this
+ */
+
+SchemaType.prototype.validateAll = function(validators) {
+  for (let i = 0; i < validators.length; i++) {
+    this.validate(validators[i]);
+  }
+  return this;
+};
+
 /**
  * Adds validator(s) for this document path.
  *
@@ -1285,6 +1300,9 @@ SchemaType.prototype.select = function select(val) {
 SchemaType.prototype.doValidate = function(value, fn, scope, options) {
   let err = false;
   const path = this.path;
+  if (typeof fn !== 'function') {
+    throw new TypeError(`Must pass callback function to doValidate(), got ${typeof fn}`);
+  }
 
   // Avoid non-object `validators`
   const validators = this.validators.
@@ -1419,7 +1437,6 @@ SchemaType.prototype.doValidateSync = function(value, scope, options) {
   let i = 0;
   const len = validators.length;
   for (i = 0; i < len; ++i) {
-
     const v = validators[i];
 
     if (v === null || typeof v !== 'object') {
diff --git a/test/schematype.test.js b/test/schematype.test.js
index 582a135c09..ad8367d0f6 100644
--- a/test/schematype.test.js
+++ b/test/schematype.test.js
@@ -281,4 +281,38 @@ describe('schematype', function() {
       });
     });
   });
+  it('demonstrates the `validateAll()` function (gh-6910)', function() {
+    const validateSchema = new Schema({ name: String, password: String });
+    validateSchema.path('name').validate({
+      validator: function(v) {
+        return v.length > 5;
+      },
+      message: 'name must be longer than 5 characters'
+    });
+    validateSchema.path('password').validateAll([
+      {
+        validator: function(v) {
+          return this.name !== v;
+        },
+        message: 'password must not equal name'
+      },
+      {
+        validator: function(v) {
+          return v.length > 5;
+        },
+        message: 'password must be at least six characters'
+      }
+    ]);
+    assert.equal(validateSchema.path('password').validators.length, 2);
+
+    const passwordPath = validateSchema.path('password');
+    assert.throws(
+      () => { throw passwordPath.doValidateSync('john', { name: 'john' }); },
+      /password must not equal name/
+    );
+    assert.throws(
+      () => { throw passwordPath.doValidateSync('short', { name: 'john' }); },
+      /password must be at least six characters/
+    );
+  });
 });
diff --git a/types/schematypes.d.ts b/types/schematypes.d.ts
index 088bc27c59..9cb4834300 100644
--- a/types/schematypes.d.ts
+++ b/types/schematypes.d.ts
@@ -192,10 +192,14 @@ declare module 'mongoose' {
     [other: string]: any;
   }
 
-  interface Validator {
-    message?: string; type?: string; validator?: Function
+  interface Validator<DocType = any> {
+    message?: string;
+    type?: string;
+    validator?: ValidatorFunction<DocType>;
   }
 
+  type ValidatorFunction<DocType = any> = (this: DocType, value: any, validatorProperties?: Validator) => any;
+
   class SchemaType<T = any, DocType = any> {
     /** SchemaType constructor */
     constructor(path: string, options?: AnyObject, instance?: string);
@@ -281,7 +285,10 @@ declare module 'mongoose' {
     validators: Validator[];
 
     /** Adds validator(s) for this document path. */
-    validate(obj: RegExp | ((this: DocType, value: any, validatorProperties?: Validator) => any), errorMsg?: string, type?: string): this;
+    validate(obj: RegExp | ValidatorFunction<DocType> | Validator<DocType>, errorMsg?: string, type?: string): this;
+
+    /** Adds multiple validators for this document path. */
+    validateAll(validators: Array<RegExp | ValidatorFunction<DocType> | Validator<DocType>>): this;
 
     /** Default options for this SchemaType */
     defaultOptions?: Record<string, any>;