That quote is a fair summation of Exodus 5 – Moses blew it the diplomatic approach the Lord had given him and the initial consequence for the people of God, who are now in slavery, is that they will have to make bricks without straw. Life has suddenly became more difficult than it already was.
Back in Exodus 3:18 God gave explicit instruction to Moses about how to approach Pharaoh:
“Then you and the elders are to go to the king of Egypt and say to him, ‘The Lord, the God of the Hebrews, has met with us. Let us take a three-day journey into the wilderness to offer sacrifices to the Lord our God.'”
As you have just read in chapter 5, Moses made 4 mistakes – and so at this stage of his leadership ministry, he is going to have to learn detailed faithfulness.
Firstly Moses was instructed to take the elders of Israel with him to see Pharaoh, but he only took Aaron.
He was meant to tell Pharaoh “The Lord, the God of the Hebrews has met with us…”. Instead he goes in like a prophetic nutter “Thus says the Lord…” – to which Pharaoh’s reply was effectively “well he hasn’t said it to me!”
Pharaoh has no idea who the “Lord” is, but the language God gave Moses that the Lord “has met with us” would have been recognised by anyone at the time, including Pharaoh, as a theophany – a god (in this case God) has appeared to them.
Pharaoh wouldn’t have heard of Israel either – but the people of God were well known as Hebrews.
Instead of a moderate request of 3 days leave of absence as a God given opening gambit, Moses goes full on and makes a demand for national emancipation.
Added to God’s word
In v3 Moses threatens plagues and slaughter. The Lord had commanded a corporate approach couched with understandable terms, to make a reasonable request in courteous terms. Instead Moses adds to what the Lord says and goes in like Donald Trump. Therefore, he reaped failure and disappointment.
Moses is still his old can do self of 3:12. But it exposed Pharaoh’s already hardened heart. And it made life difficult for the Hebrews who soon let Moses know what they thought v21!
To Moses credit, humility comes as he turns to the Lord for help. Moses is learning.
Do you go ahead of the Lord to get it done? Do you add or subtract from what He is asking you to do? Turn to Him to get it right!