Have you ever thought about what a sacrifice really is? I was reading in Exodus about the different sacrifices they made to God. They were to offer on the alter each day a lamb, once in the morning and one in the evening. The one in the morning was to be offered with flour and a hin of oil from pressed olives. A hin is about equal to a quart. That is 32 ounces. One olive will only produce about 3-5 drops of oil. Think about an eye dropper or a medicine dropper. that is not much. But those people pressed enough olives daily to make this offering. Olive oil had multiple uses like: food, health, beauty and energy, anoint people, as well as for burial. It was sometimes referred to as an ointment. The best ointments were kept in small alabaster boxes that best preserved it aroma. Some of the better ointments were known to keep their distinctive scents for centuries.
So, I would say God ask these people to make a great sacrifice just by requiring the oil to be used. It took their time and energy to produce the oil, which is over and above what they normally would need and use for their own personal use. Has God changed? NO, HE has NOT. God still requires we give Him out time and energy. God is not going to ask for something that you will come by easy. It has to stretch you. You can not go buy what God wants. The simple way is to commit to God to do His will. Give God the sacrifice He wants from you. Then He will give back to you more than you can possibly ask for. Getting up an hour or two earlier in the morning to spend time with God is hard. But the more you do it the easier it gets. Then one day, you will just wake up from an internal time clock just to spend time with Him. Then you will have to find another sacrifice. Spend another hour in the evenings. Oh, boy. Try breaking way from family and friends on a regular basis.
May God bless you ---------------------