Without Blemish!

Deuteronomy; 17:1
(You shall not sacrifice to the LORD your God a bull or sheep which has any blemish or defect, for this an abomination to the LORD your God.)
When God was instructing the people about sacrificing animals, He specifically told them that the animal had to be perfect. He didn't want their left overs which they didn't want, but He wanted the best they had to offer. If they brought in some animal that wasn't perfect, they were not showing the respect that God deserves and requires. In effect, they were failing to acknowledge God as God the provider of all the best we have.

God desires the first fruits of all we have to give. In the Old Testament, when the people gave the first of the crops to the Lord, they were saying that they had faith that God would supply all their needs through the remaining year. It is the same with us today in our giving to the Lord. God wants our first fruits as an act of faith.
Proverbs; 3:9
(Honor the LORD with your possessions, And with the firstfruits of all your increase;)
God doesn't need our money, but He wants us to give in faith and with a loving heart. By giving in this manner, we are telling Him that we are very thankful for His provisions in our life. Also we are saying that we know He will supply our needs present and future.

When God the Father sent Jesus to earth to die in our place, He sent the perfect sacrifice of all time. God the Son came to die for our sins and He needed to be perfect. Anything less than perfect would not have satisfied the requirements of a Holy God. Jesus had to be perfect and He fulfilled that requirement in that He was fully man and fully God. He was sinless and no man on earth is sinless.
Romans; 3:23
(for all have sinned and fallen short of the glory of God)
We are told that Jesus was sinless.
1Peter; 2:22-24
("Who committed no sin, Nor was deceit found in His mouth"; who, when He was reviled, did not revile in return; when He suffered, He did not threaten, but committed Himself to Him who judges righteously; who Himself bore our sins in His own body on the tree, that we, having died to sins, might live for righteousness-by whose stripes you were healed.)

So God gave everything for us and we need to give our best to Him. It cost Jesus His life for us to have eternal life. Without His shedding His blood on the cross, we would not have forgiveness of sins. It was His blood that made atonement for our soul.
Leviticus; 17:11
(For the life of the flesh is in the blood, and I have given it to you upon the altar to make atonement for your souls; for it is the blood that makes atonement for the soul.')

God Bless You!