Genesis 18:1-5 meaning

In the previous chapter The Lord appeared to Abram, and we saw that the Hebrew word translated "appeared" meant "to see," particularly to physically see with the eyes. This chapter begins with the phrase Now the LORD appeared to him. It does not tell us that Abraham knew it was God, but Abraham bows at the beginning, and as it becomes certain this is the LORD throughout the story, Abraham does not seem surprised. It seems reasonable to assume that Abraham recognized God from his previous encounter. On this visit God brings along two other visitors. 

In the last visitation, God went up from Abraham when their visit was over. In this case, Abraham lifted up his eyes and looked, behold three men were standing opposite him. Perhaps part of the clue that this is the LORD comes from what seems to be a sudden appearance, similar to the apparent sudden departure. This could be two angels along with Jesus appearing in the form of a human, prior to actually becoming a human.   

Abraham was still living in a tent by the Oaks of Mamre at Hebron (Genesis 13:18, Hebrews 11:9). It was common to take a midday rest in the heat of the day (2 Samuel 4:5) Abraham was sitting at the tent door in the heat of the day.

"He lifted up his eyes and looked, behold, three men were standing opposite him. They appear suddenly out of nowhere, which immediately suggests they were not ordinary men. Although they are perceived to be human, we discover that of these three heavenly messengers; one is God and two are angels (Genesis 16:7, 18:17, 19:1). Later, the two angels will go toward Sodom while God and Abraham discuss the fate of Sodom and Gomorrah. 

The next few verses (verses 2-8) illustrate seven ways Abraham shows hospitality. First, he ran from the tent door to meet them. Abraham is a model of unselfish and enthusiastic hospitality. Abraham saw they were tired and promptly offered them rest and food. The Bible tells us, "do not neglect to show hospitality to strangers, for by this some have entertained angels without knowing it" (Hebrews 13:2). Second, he bowed himself to the earth. At the age of 99, not only did Abraham run to meet the visitors, he bowed himself before them. Bowing was a physical gesture and a courteous way of showing honor and respect to a superior person or King (Genesis 43:28). An elderly man of some social stature would not normally respond in this way to visitors, but in this case it seems Abraham recognized who he was speaking with.

Third, Abraham calls him Lord which is a courteous title comparable to the modern greeting "sir." Abraham acted as if it would be a favor to him if they allowed him to serve them, saying, If now I have found favor in Your sight, please do not pass Your servant by.  Since it appears that Abraham recognized God, it is fitting he would consider it an honor to serve them. This shows the wisdom of Abraham. We are told in Revelation 3:18-20 that true riches, all the gold we want, comes from hearing the voice of God and opening the door of our hearts. Jesus states that if anyone does this He will come in to him and will dine with him, and he with Me.

It was it custom to take off your shoes and wash your tired feet which Abraham suggested let a little water be brought and wash your feet. In the ancient world, the unpaved roads were very dusty, and travelers wore sandals. Consequently, when they came to some stopping place, it was refreshing and cleansing to have their feet washed. This was known as genuine hospitality and an act of politeness that made them feel at home (Genesis 19:2, 24:19, 32, 43:24, Judges 19:21, 2 Samuel 11:8, Luke 7:44, John 13:5, 1 Timothy 5:10). Besides feeding the travelers, he ensures that they are rested and refreshed telling them to rest yourselves under the tree and bringing a piece of bread.