The Posuk says:
וַיִּיטַב בְּעֵינַי, הַדָּבָר; וָאֶקַּח מִכֶּם שְׁנֵים עָשָׂר אֲנָשִׁים, אִישׁ אֶחָד לַשָּׁבֶט
Transalation: It was good in his eyes
What was Moshe's complaint if it was good in his eyes that they spied?
Rashi answers with an example someone was selling a donkey the buyer wanted to test the man to see if it was in good health.He asked him for a test drive, he said fine, now he knew it was in good health, but he wanted to really make sure.He then asked how about the mountains can I take it there, the seller quickly answered yes.The buyer now understood if he was allowing it to be tested in such a strenuous manner it was a good product, so he bought it. This should also have been the response of Klal Yisroel. You want to know about the land fine Hashem allows you to spy it out.It was good in Moshe's eyes, now take his word and make the purchase they did not they wanted to see it themselves, and hence Moshe chastised them.