The question seems simple enough to answer, yet the practice of ensuring one's attitude and conduct reflect one's obvious verbal response to the question is much more difficult. The question is: Is anything impossible for God? Of course anyone who believes in God and knows God would resoundingly answer, "no!" However, even those who possess saving faith struggle to live in ways that reflect one's answer to that question. In other words, its easy to verbally answer the question correctly; but its much more difficult to live according to the answer. Nevertheless, the answer is true - nothing is impossible for God.
In Genesis 18:1-15 the Bible shows God paying a visit to Abraham in the form of Jesus. Yes - Jesus appeared to Abraham in the Old Testament just as Jesus said He did in the New Testament (John 8:56). In Genesis 18:1-15 the Bible describes that 3 men visited Abraham. Seemingly a few days after God had given the instruction of circumcision, God desired to confirm His promise that Abraham would have a son by Sarah in person. Thus, the scriptures show that 3 men visited Abraham, one of which was the Lord Himself. The Bible testifies that as Abraham saw the men coming, he immediately recognized the authority of the Lord and sought to take care of Him and the two other men He was with. The Bible shows that Abraham stopped what he was doing, ran to Sarah, asked her to make some bread, found a calf, had it slaughtered, and made a meal to give to the Man that he referred to as "my Lord."
The scriptures describe a much different Abraham from Genesis chapter 17 to Genesis chapter 18. In Genesis chapter 17 the Lord called out to Abraham, but after 14 years of distance from one another. So when God called out to Abraham in Genesis chapter 17, Abraham was caught off guard and humbled, being commanded to repent. In Genesis chapter 18, after God had demonstrated more grace and re-confirmed His promises towards Abraham for the third time, and even changed his name, Abraham is not in a need to repent, but instead is in position to serve. The repentance of Abraham in Genesis chapter 17, and his understanding of God's promises, and his obedience to God's command made it so that Abraham was able to serve the Lord. Abraham was able to recognize the identity of the Lord and was in a position of preparedness to offer up his best meat and good bread to bring it before the Lord and take care of Him.
Genesis 18:1-15 goes on to explain the purpose of the Lord's visit. As the men ate with Abraham, the Lord asked where Sarah was. Abraham simply answered that Sarah was in the tent. Then the Bible explains that the Lord said that Sarah would certainly have a son within the year. The Lord said that He would come back in about a year and that by that time, Sarah would have a son. God transformed His appearance into the form of a man as He did in Jesus, in order to confirm His everlasting and unconditional promises. This is exactly what God did in Christ!
The scriptures then candidly display the folly of humanity. Though God had confirmed His promise to give Abraham and Sarah a child of their own 4 different times, and even came into the world Himself to confirm the fourth time, the Bible states that as Sarah was eavesdropping on the conversation, she laughed at the idea of her having a baby at 90 years old. She couldn't believe that it was possible. Sarah didn't laugh to mock the Lord, but the idea of a 90 year old woman having a baby seemed ridiculous to her as it would to someone today. Sarah understood her physical circumstances and limitations. The Bible even confesses that Sarah was well over the age of child-bearing, even though people were still living much longer than people today during that time.
The Bible explains that the Lord heard Sarah's laugh - of course He did, He's God! Hence, the scriptures show that the Lord inquired to Abraham (as they were still conversing) why Sarah was laughing at the idea of having a child. Then the Lord asked the question that seems to plague the lives of all believers: Is anything impossible for the Lord?
Consider the position of a believer. A Bible-believing Christian should place trust in the authority of God's Word as being infallible as the literal Word of the Living God. Knowing this, a believer should trust that God spoke the world into existence. In doing so, God brought order to what was once chaos. God brought form to that which had no form. God created everything out of nothing. God judged the whole world with a flood and hand selected 8 people and a God-sized handful of animals to restore the planet. God overpowered the will of mankind to band together in "unity" (also known as rebellion) and spread out human life all over the face of the earth according to His will. God spoke clearly to Abraham. God led Abraham into safety in Canaan, rescued Abraham from bad situations in Egypt, sustained Abraham during the famine, and gave Abraham a great victory as an old man. If God can do all of these things, is there anything that God cannot do? If God is limited in ability, then He ceases to be God. The fact that God created everything out of nothing is proof that God can do all things because as Creator, He is in charge over all things and has demonstrated this truth throughout the history of mankind - especially through the bloodline of Abraham and the nation of Israel!
If one were to examine the resume of God as laid out in the scriptures, the question is simple to answer. Nothing is impossible for God. Yet Genesis 18:1-15 shows that, though Abraham and Sarah would have been able to verbally answer that question correctly, they continued to live in ways to show that they doubted the ability of the Living God. Consider that as Sarah laughed, she may have done so in the presence of her 13-year old step son - the living proof that she didn't trust God as much as she might have been willing to verbally confess. In fact, the scriptures reveal that Sarah had such little faith in the ability of God that she even tried to lie about her laughing at the Lord's promise of a son, as if the Lord couldn't hear her and see the doubt in her heart. The scriptures explain that Sarah was afraid. She had been caught doubting the Lord. While she might have said that the Lord could do anything, she didn't think it was likely that He would do those things for her, and laughed at the idea that God would be able to fulfill His promises. When the Lord exposed her unbelief, she became afraid.
This scripture presents great difficulty from the human perspective, but great comfort at the same time when one examines the response (or lack thereof) of the Lord. It is difficult to acknowledge that many believers are quick to verbally profess the Lord, but all have the natural inclination to lack in faith. Believers understand the almighty nature, faithfulness, and loving character of God, but often times doubt that He would be willing to demonstrate Himself as such in our own lives. Many times the circumstantial events of one's life can cause one to think that God is somehow limited in His capacity. Can the God who spoke the universe into creation and made everything out of nothing really be limited? Is God weary? Did God forget about His promises to His children? Did the God of the universe somehow overlook our needs and concerns? The truth of the matter is that the problem of a believer is rooted in the expectation of a believer. As people, it is often true that our expectations are different that the will of God so that when our expectations are not met, the circumstances seem to be greater than what they really are, and fear/doubt naturally arise. Sarah's expectations were to have a child long before she did. Sarah expected to have a child as soon as God made the promise. After waiting 10 years, Sarah's expectation was to have a child then. Yet because of her own limitations as a human being, she was unable and brought Hagar into the picture. Sarah's expectations were then shifted. She expected to have peace in the midst of chaos that she helped create. Then, when the Lord Himself showed up to clean up the mess and fulfill His promise, she expected that it was too late. Her expectations were seldom in line with the will of God.
However, the beautiful part of this testimony is the Lord's response to Sarah's lapse in faith. Though Sarah demonstrated unbelief, the Lord did not condemn her. The Lord had the right to rescind His promise and punish Sarah, but the scriptures don't show that happening. Instead, the scriptures show that the Lord pointed out the disbelief in Sarah, and show that when she tried to lie about laughing, He simply restated the truth that she did laugh, causing her to have to deal with the reality of her disbelief in repentance. Then the Lord simply carried on. He continued to do the necessary work to fulfill His promise. He never threatened to take away the promise of a son. He never said that Sarah was undeserving of a son - she wasn't deserving when God first made the promise. Once again, the conduct of humanity has no bearing on the faithfulness of God to do as He promised. The grace of God is too much! Even though Sarah felt that God was limited in ability, God continued to move forward to prove her wrong, and the next year, Sarah experienced the truth. Nothing is impossible for God - no matter how much mankind may think otherwise!