diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 9040c0d..99a06fc 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -5869,9 +5869,13 @@
 
 	if (cmp == 0)
 	{
-	    if (!force)
+	    // Command can be replaced with "command!" and when sourcing the
+	    // same script again, but only once.
+	    if (!force && (cmd->uc_script_ctx.sc_sid != current_sctx.sc_sid
+			  || cmd->uc_script_ctx.sc_seq == current_sctx.sc_seq))
 	    {
-		EMSG(_("E174: Command already exists: add ! to replace it"));
+		EMSG2(_("E174: Command already exists: add ! to replace it: %s"),
+									 name);
 		goto fail;
 	    }