Well, God had seemingly told him to kill his only son, and give him as a burnt offering. He was ready to kill him so, until God stopped him and praised his faith in God. Also, he was told to leave his country and go to Haran. And leave his father's house to a land which God would show him.
According to the Torah, God tested Abraham's faith and obedience many times. The final test was the hardest. It was common at that time to offer animals as a sacrifice. They would be slaughtered and burnt on an alter. in his old age, Abraham had finally fathered a son, Isaac. The Torah says that one day God tested Abraham by seemingly telling him to make a sacrifice of his son. Abraham dearly loved his son. Yet his devotion to God was so complete that he brought Isaac to a mountain to be sacrificed. When God saw this He sent an angel down to stop Abraham from killing his son. Abraham had shown his faith and obedience. God said, "I will make your descendants as many as the stars of heaven." God kept the promise, and the Hebrews flourished. The nation became 12 tribes that were descendants of Abraham's grandson, Jacob, whom an angel from God renamed Israel.
Abraham showed his faith by being willing to offer his son Isaac on an altar to God, as a test of his obedience and trust in God's promises. However, God provided a ram for the sacrifice instead, recognizing Abraham's faith and obedience.
Abraham was chosen by God because of his faith and obedience. God saw that Abraham would trust Him and follow His commands, making him a suitable vessel to carry out God's plan for the world.
God chose Abraham because of his faith and obedience. Abraham demonstrated unwavering trust in God and was willing to follow His commands, making him a suitable vessel for God's plan to establish a covenant with his descendants.
Because it showed that God was keeping his promise (Genesis 15:13-14) to Abraham, and it showed that God can change the laws of nature at will.
God called Abraham righteous because of his faith and obedience. Abraham trusted in God's promises, demonstrated by his willingness to leave his homeland and obey God's commands, such as when he was prepared to sacrifice his son Isaac. This faith and obedience showed Abraham's righteousness before God.
God was angry at David for taking a census because it showed a lack of trust in God's protection and provision.
God chose Abraham to be the father of many nations because of his faith and obedience. Abraham demonstrated unwavering trust in God and followed His commands, making him a suitable vessel for God's plan to bless all nations through his descendants.
He did not kill Isaac. He showed readiness to do so if that was God's command, and God then told him that it was a test (see Genesis ch.22).
As you may already know, Abraham and his wife Sarah, were both really old when they had Isaac. As a test, God told Abraham to sacrifice his son. If he had enough faith in God, he wouldn't have to worry about what happened to his son. Abraham took his son up to the altar and Isaac asked what they were offering. Abraham said, "The LORD will provide the offering." Abraham tied his son to the altar and prepared to kill him when an angel of the LORD appeared to him. He told Abraham to let his son go, he had showed his faith in God. Abraham had passed the test.
Abraham chose God before God chose him. Abraham, on his own, had rejected the idols his family and country worshiped and intuitively followed the teachings of the Torah. It's for this reason that he is considered the spiritual forefather of the Jews besides his being their ancestor.
God did not offer Abraham any "religion" in the sense of a defined philosophy with a name. He only made the covenant. Abraham was made to understand that there was only one God, whom he had to trust. In return, God would bless him, and would eventually bless the whole world through Abraham's descendants. There were no rituals. There was not even a moral code. All that came later.
Lots of things, but one of the most famous was a test of his trust. God asked Abraham to sacrifice his son (the Muslim and Christian interpretations of this debate over which son). Abraham doesn't want to kill his son, but if God says so, he figures he has to. Right before he was going to, however, God told him he essentially passed the test.