Genesis 18 and 20 make for another interesting contrast. Here we have a very full three month period of time. I say three months, because we know that God has promised Isaac in a year, and his conception takes place in chapter 21 after Sodom and Gomorrah are destroyed, and Abram has journeyed south and pitched camp in Gerar. In chapter 18, Abram is visited by two angels (the ones that continue on to Sodom and Gomorrah) and a Theophany. Abraham recognizes His Lord and shows appropriate hospitality. At this time, Sarah also hears God's intention to give she and Abraham a child, and she hears it from God's own mouth. What has been a promise to her husband from her husband's God, becomes a personal promise to her from her God. As the travelers prepare to leave and head toward the plain, Abraham is invited to walk along with them, and God reveals His plan for the destruction of Sodom and Gomorrah. Abram boldly pleads with God to consider mercy if the angels find even ten righteous men in the city. He no doubt is pleading for his nephew Lot's sake especially. Having God's promise that the cities will be spared for the sake on ten righteous, Abraham returns home.
From Abraham's perspective, though we're not given these details, the next few days must have been horrific. His camp was right over the mountain ridge from a disaster. The sky was likely black from the storm of God's judgement--screams audible--thunder, lightening, and fire visible. The air was probably thick with soot and ash. Whether Abraham moved his camp south out of fear or necessity, we do not know, but move south he did--toward Kadesh where Abimelech was the ruler.
Here we see a previous side of Abraham return--the side of him easily overcome by fear--and in the presence of that fear, Abraham gives into an old sin. In chapter 20, we see a repeat performance of Abraham's early trip into Egypt. He tells Sarah to say she is his sister, so the men in the land will not kill him for his wife. The results of Abraham's half-truth are very similar to the results which occurred in Egypt. The king takes Sarah, intending to add her to his wives, God curses Abimelech's house, and Abraham is forced to 'fess up. By God's grace, Abraham is allowed to stay in the area (they kicked him out of Egypt), but it must have been an awkward and poor start in their new location.
What occurred to me as I read these accounts was simply this: obedience to God draws us near to God and makes us bold with Him. When we allow ourselves to be distracted by circumstances around us, we lose clear spiritual sight and fall prey to fear and sin. Abraham's swift obedience to God in regards to circumcision was followed by a season of fellowship and boldness. When he set his eyes on the disaster of Sodom, he became fearful and returned to an old sin. Everyone of us has experienced this cycle, so may we be mindful and keep our eyes on God and our hearts set on obedience!