diff --git a/pkg/kn/commands/configuration_edit_flags.go b/pkg/kn/commands/configuration_edit_flags.go
index 2cc4b7240..8f24e158f 100644
--- a/pkg/kn/commands/configuration_edit_flags.go
+++ b/pkg/kn/commands/configuration_edit_flags.go
@@ -54,7 +54,7 @@ func (p *ConfigurationEditFlags) AddCreateFlags(command *cobra.Command) {
 	command.MarkFlagRequired("image")
 }
 
-func (p *ConfigurationEditFlags) Apply(config *servingv1alpha1.ConfigurationSpec) error {
+func (p *ConfigurationEditFlags) Apply(config *servingv1alpha1.ConfigurationSpec, cmd *cobra.Command) error {
 	envMap := map[string]string{}
 	for _, pairStr := range p.Env {
 		pairSlice := strings.SplitN(pairStr, "=", 2)
@@ -69,9 +69,11 @@ func (p *ConfigurationEditFlags) Apply(config *servingv1alpha1.ConfigurationSpec
 	if err != nil {
 		return err
 	}
-	err = servinglib.UpdateImage(config, p.Image)
-	if err != nil {
-		return err
+	if cmd.Flags().Changed("image") {
+		err = servinglib.UpdateImage(config, p.Image)
+		if err != nil {
+			return err
+		}
 	}
 	limitsResources, err := p.computeResources(p.LimitsFlags)
 	if err != nil {
diff --git a/pkg/kn/commands/service_create.go b/pkg/kn/commands/service_create.go
index 9159f0718..bda6eaa33 100644
--- a/pkg/kn/commands/service_create.go
+++ b/pkg/kn/commands/service_create.go
@@ -75,7 +75,7 @@ func NewServiceCreateCommand(p *KnParams) *cobra.Command {
 			if err != nil {
 				return err
 			}
-			err = editFlags.Apply(config)
+			err = editFlags.Apply(config, cmd)
 			if err != nil {
 				return err
 			}
diff --git a/pkg/kn/commands/service_update.go b/pkg/kn/commands/service_update.go
index e818a211e..0d80e5b9a 100644
--- a/pkg/kn/commands/service_update.go
+++ b/pkg/kn/commands/service_update.go
@@ -58,7 +58,7 @@ func NewServiceUpdateCommand(p *KnParams) *cobra.Command {
 			if err != nil {
 				return err
 			}
-			err = editFlags.Apply(config)
+			err = editFlags.Apply(config, cmd)
 			if err != nil {
 				return err
 			}
diff --git a/pkg/kn/commands/service_update_test.go b/pkg/kn/commands/service_update_test.go
index d87353ba7..c064ebb7c 100644
--- a/pkg/kn/commands/service_update_test.go
+++ b/pkg/kn/commands/service_update_test.go
@@ -108,6 +108,51 @@ func TestServiceUpdateImage(t *testing.T) {
 	}
 }
 
+func TestServiceUpdateEnv(t *testing.T) {
+	orig := &v1alpha1.Service{
+		TypeMeta: metav1.TypeMeta{
+			Kind:       "Service",
+			APIVersion: "knative.dev/v1alpha1",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "foo",
+			Namespace: "default",
+		},
+		Spec: v1alpha1.ServiceSpec{
+			RunLatest: &v1alpha1.RunLatestType{},
+		},
+	}
+
+	config, err := servinglib.GetConfiguration(orig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	servinglib.UpdateImage(config, "gcr.io/foo/bar:baz")
+
+	action, updated, _, err := fakeServiceUpdate(orig, []string{
+		"service", "update", "foo", "-e", "TARGET=Awesome"})
+
+	if err != nil {
+		t.Fatal(err)
+	} else if !action.Matches("update", "services") {
+		t.Fatalf("Bad action %v", action)
+	}
+	expectedEnvVar := corev1.EnvVar{
+		Name:  "TARGET",
+		Value: "Awesome",
+	}
+
+	conf, err := servinglib.GetConfiguration(updated)
+	if err != nil {
+		t.Fatal(err)
+	} else if conf.RevisionTemplate.Spec.Container.Image != "gcr.io/foo/bar:baz" {
+		t.Fatalf("wrong image set: %v", conf.RevisionTemplate.Spec.Container.Image)
+	} else if conf.RevisionTemplate.Spec.Container.Env[0] != expectedEnvVar {
+		t.Fatalf("wrong env set: %v", conf.RevisionTemplate.Spec.Container.Env)
+	}
+}
+
 func TestServiceUpdateRequestsLimitsCPU(t *testing.T) {
 	service := createMockServiceWithResources(t, "250", "64Mi", "1000m", "1024Mi")