"In Genesis 18.1-8, there are three travelers moving down the road and are met by Abraham. He invites them in, showing hospitality, and prepares a big meal for them. We find out that one of them is the LORD. V.8 says, and Abraham "stood by them under the tree while they ate." Abraham serves and then observes the meal of divine refreshment, but he does so at a distance, standing over there at the oak of Mamre.
As the story of God’s world rescue operation deepens, God will later have the Levites and Priests regulate who and how only the people, Israel, may approach the table and minister to the LORD. And then later still, the LORD himself comes in flesh and blood promising that “many will come from east and west and recline at table with Abraham, Isaac and Jacob in the kingdom of heaven” (Matthew 8.11); and then he makes good this promise by preparing the table of the LORD by giving His body, and the cup of the new covenant in His blood, given for many for the remission of sins. You see the movement in the Bible's story-line from a table for the Lord by the oaks of Mamre, to the table of the Lord, prepared and served by the Lord and made open by His sacrifice.
This table is open to all, to anyone who has a true sense of their sin and a grasp of the mercy of God in Christ, who have professed their confident assurance in Jesus that He loved you and gave Himself for you; who have been marked as belonging to Jesus in Christian baptism; and are joined to a God-fearing, Christ-loving, Bible-believing, Gospel-embracing Christian congregation. You no longer need watch from a distance, nor are you excluded by race, ethnicity, social standing, or denominational affiliation. The Lord Jesus himself calls you to his table, to receive Him in your hearts, by faith, with thanksgiving."