diff --git a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/util/json/ParameterBindingJsonReaderUnitTests.java b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/util/json/ParameterBindingJsonReaderUnitTests.java
index 2b940e6cb..33105d265 100644
--- a/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/util/json/ParameterBindingJsonReaderUnitTests.java
+++ b/spring-data-mongodb/src/test/java/org/springframework/data/mongodb/util/json/ParameterBindingJsonReaderUnitTests.java
@@ -15,7 +15,8 @@
  */
 package org.springframework.data.mongodb.util.json;
 
-import static org.assertj.core.api.Assertions.*;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 
 import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
@@ -30,7 +31,6 @@ import org.bson.BsonRegularExpression;
 import org.bson.Document;
 import org.bson.codecs.DecoderContext;
 import org.junit.jupiter.api.Test;
-
 import org.springframework.data.expression.ValueExpressionParser;
 import org.springframework.data.spel.EvaluationContextProvider;
 import org.springframework.data.spel.ExpressionDependencies;
@@ -104,6 +104,22 @@ class ParameterBindingJsonReaderUnitTests {
 		assertThat(pattern.getOptions()).isEqualTo("i");
 	}
 
+	@Test // GH-4806
+	void treatsQuotedValueThatLooksLikeRegexAsPlainString() {
+
+		Document target = parse("{ 'c': '/^?0$/i' }", "foo");
+
+		assertThat(target.get("c")).isInstanceOf(String.class);
+	}
+
+	@Test // GH-4806
+	void treatsStringParameterValueThatLooksLikeRegexAsPlainString() {
+
+		Document target = parse("{ 'c': ?0 }", "/^foo$/i");
+
+		assertThat(target.get("c")).isInstanceOf(String.class);
+	}
+
 	@Test
 	void bindValueToRegex() {
 
@@ -147,7 +163,6 @@ class ParameterBindingJsonReaderUnitTests {
 	@Test
 	void bindListValue() {
 
-		//
 		Document target = parse("{ 'lastname' : { $in : ?0 } }", Arrays.asList("Kohlin", "Davar"));
 		assertThat(target).isEqualTo(Document.parse("{ 'lastname' : { $in : ['Kohlin', 'Davar' ]} }"));
 	}
@@ -155,7 +170,6 @@ class ParameterBindingJsonReaderUnitTests {
 	@Test
 	void bindListOfBinaryValue() {
 
-		//
 		byte[] value = "Kohlin".getBytes(StandardCharsets.UTF_8);
 		List<byte[]> args = Collections.singletonList(value);
 
@@ -170,12 +184,9 @@ class ParameterBindingJsonReaderUnitTests {
 		assertThat(target).isEqualTo(Document.parse("{ \"id\" : { \"$exists\" : true}}"));
 	}
 
-	// {'id':?#{ [0] ? { $exists :true} : [1] }}
-
 	@Test
 	void bindDocumentValue() {
 
-		//
 		Document target = parse("{ 'lastname' : ?0 }", new Document("$eq", "Kohlin"));
 		assertThat(target).isEqualTo(Document.parse("{ 'lastname' : { '$eq' : 'Kohlin' } }"));
 	}
@@ -183,7 +194,6 @@ class ParameterBindingJsonReaderUnitTests {
 	@Test
 	void arrayWithoutBinding() {
 
-		//
 		Document target = parse("{ 'lastname' : { $in : [\"Kohlin\", \"Davar\"] } }");
 		assertThat(target).isEqualTo(Document.parse("{ 'lastname' : { $in : ['Kohlin', 'Davar' ]} }"));
 	}
@@ -191,7 +201,6 @@ class ParameterBindingJsonReaderUnitTests {
 	@Test
 	void bindSpEL() {
 
-		// "{ arg0 : ?#{[0]} }"
 		Document target = parse("{ arg0 : ?#{[0]} }", 100.01D);
 		assertThat(target).isEqualTo(new Document("arg0", 100.01D));
 	}
@@ -331,9 +340,8 @@ class ParameterBindingJsonReaderUnitTests {
 
 		String json = "{ $and : [?#{ [0] == null  ? { '$where' : 'true' } : { 'v1' : { '$in' : {[0]} } } }]}";
 
-		ExpressionDependencies expressionDependencies = new ParameterBindingDocumentCodec()
-				.captureExpressionDependencies(json, it -> new Object(),
-						ValueExpressionParser.create(SpelExpressionParser::new));
+		ExpressionDependencies expressionDependencies = new ParameterBindingDocumentCodec().captureExpressionDependencies(
+				json, it -> new Object(), ValueExpressionParser.create(SpelExpressionParser::new));
 
 		assertThat(expressionDependencies).isEqualTo(ExpressionDependencies.none());
 	}
@@ -343,9 +351,8 @@ class ParameterBindingJsonReaderUnitTests {
 
 		String json = "{ hello: ?#{hasRole('foo')} }";
 
-		ExpressionDependencies expressionDependencies = new ParameterBindingDocumentCodec()
-				.captureExpressionDependencies(json, it -> new Object(),
-						ValueExpressionParser.create(SpelExpressionParser::new));
+		ExpressionDependencies expressionDependencies = new ParameterBindingDocumentCodec().captureExpressionDependencies(
+				json, it -> new Object(), ValueExpressionParser.create(SpelExpressionParser::new));
 
 		assertThat(expressionDependencies).isNotEmpty();
 		assertThat(expressionDependencies.get()).hasSize(1);