Genesis 18:1-15 NIV
 The Lord appeared to Abraham near the great trees of Mamre while he was sitting at the entrance to his tent in the heat of the day.  Abraham looked up and saw three men standing nearby. When he saw them, he hurried from the entrance of his tent to meet them and bowed low to the ground.  He said, “If I have found favor in your eyes, my lord, do not pass your servant by.  Let a little water be brought, and then you may all wash your feet and rest under this tree.  Let me get you something to eat, so you can be refreshed and then go on your way---now that you have come to your servant.” “Very well,” they answered, “do as you say.”  So Abraham hurried into the tent to Sarah. “Quick,” he said, “get three seahs of the finest flour and knead it and bake some bread.”  Then he ran to the herd and selected a choice, tender calf and gave it to a servant, who hurried to prepare it.  He then brought some curds and milk and the calf that had been prepared, and set these before them. While they ate, he stood near them under a tree.  “Where is your wife Sarah?” they asked him. “There, in the tent, ” he said.  Then one of them said, “I will surely return to you about this time next year, and Sarah your wife will have a son.” Now Sarah was listening at the entrance to the tent, which was behind him.  Abraham and Sarah were already very old, and Sarah was past the age of childbearing.  So Sarah laughed to herself as she thought, “After I am worn out and my lord is old, will I now have this pleasure?”  Then the Lord said to Abraham, “Why did Sarah laugh and say, 'Will I really have a child, now that I am old?'  Is anything too hard for the Lord? I will return to you at the appointed time next year, and Sarah will have a son.”  Sarah was afraid, so she lied and said, “I did not laugh.” But he said, “Yes, you did laugh.”
Right from the start, the reader knows the identity of at least one of the three visitors who mysteriously appear to Abraham while he's resting under a tree in the sun:
"The Lord appeared to Abraham..." (v. 1)
One of them was either God Himself in physical form or represented God. The other two were angels. As I said yesterday, angels break all the typical stereotypes. They are not dearly departed loved ones who are given a set of wings as a reward for their good behaviour. Rather they are spiritual beings, created by God, to work with us humans to fulfil His purposes on the earth. Hebrews 1: 14 makes this very clear:
"Are not all angels ministering spirits sent to serve those who will inherit salvation?"
Think about this with me. The role of ALL angels is to minister to Christians and serve us. I find that incredible. It makes me wonder how often I have missed the activity and presence of angels in my own life.
The events of chapter 18 happened only days after chapter 17, so it is very possible that Abraham was sitting there thinking through the incredible promises God had given him a few days earlier. There are plenty of clues which suggest that he was waiting expectantly for God to do something.
First, he rushes to meet the three visitors and literally worships the leader of the three. He calls him Adonai, or Lord, which is the same word he uses in verses 27, 30 and 32 when he is convinced that he is speaking to God himself. Abraham had not allowed the pain of waiting to cause his faith in God’s promises to waver, and he was always on the look-out for the moment when the Lord would appear to announce that the time had finally come. Abraham’s was an active, not passive, waiting.
Abraham’s extra effort to extend hospitality suggests he recognised something special in them, but we see nothing significant until the meal was served. When they demonstrate intimate knowledge shared only between Abraham and God, it becomes clear that they are envoys of heaven, more than mere humans.
While angels are spirit beings, like their Maker, they can take physical form. In this case, they appeared as humans. Not mere apparitions - they could be touched, they talked, and they ate and drank.
Sarah, perhaps curious as to what has her husband in such a fuss, stands just inside the tent where she can hear Abraham's conversation with the visitors without being seen. However, she give her presence away when she hears the angelic pronouncement:
"I will surely return to you about this time next year, and Sarah your wife will have a son." (v. 10)
Sarah can't help herself laughing out loud, it all sounds so incredibly ridiculous to her. As Charles Swindoll writes: "Put in today’s terms, she thought, I’m no spring chicken; I’m more like a dying hen. And he’s no Italian stallion anymore. Everything hurts . . . and what doesn’t hurt, doesn’t work!"
The question asked in response to Sarah’s doubt is one we must all honestly ask ourselves:
"Is anything too hard for the Lord?" (v.14).
We have a tendency to think of God’s ability in relation to degrees of difficulty. Praying for someone's headache - probably easy enough for God to heal. Praying for a relative with a brain tumour - let's be honest - we're not so confident. Is one really more difficult for the Lord than the other?
There’s absolutely nothing wrong with praying passionately and interceding fervently, but not because there are degrees of difficulty or because we need to get God’s attention emotionally.
"Is anything too hard for the Lord?" (v.14).
This last phrase is the key of both Sarah’s and Abraham’s stories. And it is also the key to our stories.
Time and time again, they, and we, are faced with difficult circumstances and seemingly impossible situations. Yet every single time, God makes Himself present and asks the same question, whether explicitly or implicitly: Is anything too difficult for me?
Financial problems, work issues, family drama, health scares - is anything too difficult for Him?
God is watching over you. Nothing you are facing today is too hard or stressful for Him. He knows exactly what He is doing. Your struggle is no surprise to Him and Your doubt does not slow Him down. Keep trusting, keep praying, keep waiting.