Floyd Mayweather may have taken his cue from Manny Pacquiao's advice to fear God when he posted on Instagram that "God is first in my life".

Mayweather, the 37-year-old undefeated boxer and currently five-division champion, congratulated his friend, Justin Bieber, on the singer's new jet on Instagram. The boxer then decided to defend himself on his priorities and his view on God.

He reasoned that owning a 14-passenger jet is a motivation to others to 'win' in life. He admitted that he is guilty of being materialistic and being motivated by money but rebutted at the end that God is still first in his life.

"Yes, I got a 14 passenger jet. Got to give them another reason to hate, but I will motivate the people that are ambitious and want to be winners in life," Mayweather wrote on Instagram.

"I am guilty! I'm materialistic and I'm motivated by money ... but GOD is first in my life." 

He further stated, "GOD will not give you anything you can't handle. That's why GOD gave me the best hands in the business to pray with, box with and count money with.#AirMayweather."

Mayweather likes to take swipes at fellow boxing champion Manny Pacquiao. Everyone recalls his insults on "Miss Pac Man" over social media when he shared some pictures on his Instagram page of the Filipino boxing champion knocked to the floor by his previous opponents. "Miss Pac Man is broke for a pay day," he smirked on his Twitter page.

Manny Pacquiao seems unaffected with his boxing rival and has recently remarked that Mayweather should look more to God.

In responding to Mayweather's jibes, Pacquiao went back to his Christian faith, AFP news agency reports.

"He (Mayweather) should fear God," Pacquiao said, advising him to heed the biblical passage reading "For what is a man profited if he shall gain the whole world and lose his own soul?"

The Filipino champ is a committed Christian and apparently regards Rick Warren's book "The Purpose Driven Life" as being instrumental in his coming to faith. He has previously said he and his team memorise Scripture together.

Pacquiao is deeply religious, praying at his fights and holding Bible studies with his team. His faith certainly plays a major part on his calm reaction to Mayweather's insults as he urges him to fear God.

Boxing fans have been desperate to see Pacquiao and Mayweather fight it out in the ring. Both men have exceptional fighting records, Mayweather stands undefeated in 47 fights, while Pacquiao has had an impressive 56 wins.