“The mother of the sons of Zebedee approached Jesus with her sons and did him homage, wishing to ask him for something. He said to her, "What do you wish?" She answered him, "Command that these two sons of mine sit, one at your right and the other at your left, in your Kingdom." Jesus said in reply, "You do not know what you are asking. Can you drink the chalice that I am going to drink?" They said to him, "We can." He replied, "My chalice you will indeed drink, but to sit at my right and at my left, this is not mine to give but is for those for whom it has been prepared by my Father." -Matthew 20:20-23
Jesus said, “You do not know what you are asking”, and truly no one can understand what living in the Kingdom of God will be like. First or last will not matter, our only care will be that we are in the presence of the Most Holy Trinity. In God’s Kingdom, our only focus, our only happiness, our only thought, our only reason, our everything, will be our Lord. I once glimpsed the Glory of the Holy Spirit. I wasn’t in the Kingdom, but I tell you, I never wanted to leave or turn my eyes away from Him. He is bliss and happiness, the likes of which we will never feel on Earth. If it is the chalice of Christ that we must drink to be with Him in the Kingdom, then we should grasp it eagerly. First or last with God does not matter, that we are with Him for all eternity, is our only care.