But Samuel replied, “I will not go back with you! Since you have rejected the LORD’s command, he has rejected you as king of Israel.”

1 Samuel 15:26

“One could make a thousand sacrifices for God, work a thousand hours for God’s service, or give millions of dollars to His work. But all these sacrifices mean little if there is not a surrendered heart to God, shown by simple obedience.” - David Guzik

We can: 

• Obey without love.
• Submit without love.

However, God doesn’t desire a robotic faith; He desires a loving relationship.

God wanted the Israelites to love Him.

• And you must love the LORD your God with all your heart, all your soul, and all your strength.
  Deuteronomy 6:5

God wants us to love Him.

• And you must love the Lord your God with all your heart, all your soul, all your mind, and all your strength.’ The second is equally important: ‘Love your neighbor as yourself.’ No other commandment is greater than these.”
  Mark 12:30-31

When our love reaches this level, obedience and submission isn’t rote or robotic, it's a natural response.

The elders joined the sacrifice with Jesse’s family.

“Yes,” Samuel replied. “I have come to sacrifice to the LORD. Purify yourselves and come with me to the sacrifice.” Then Samuel performed the purification rite for Jesse and his sons and invited them to the sacrifice, too.
1 Samuel 16:5

Love God, Jesus, and Holy Spirit with all my heart, mind, soul and strength.