The pair paid tribute to former President Carter at his state funeral on Thursday, performing John Lennon's "Imagine."

WASHINGTON ― The current and former living U.S. presidents said goodbye to Jimmy Carter on Thursday, and in the process once again highlighted the contrast between former and soon-to-be President Donald Trump and all the others.

Donald Trump could learn a lot from the 39th president’s commitment to honesty, human rights, and self-improvement.

Funeral services for former President Jimmy Carter began Saturday as the U.S. pays respect to the 39th president who passed away last Sunday at 100 years old. The nation will honor Carter over six days of funeral events.

Obama, who attended without his wife, Michelle, shared a second-row pew with former presidents George W. Bush and Bill Clinton, along with their spouses. President Joe Biden and first lady Jill Biden arrived last and sat in the pew just in front of them.

When Joe Biden eulogized Jimmy Carter today in the majestic surroundings of Washington National Cathedral today, he said of his predecessor, “Many think he was from a bygone era, but he saw into the future.

Former President Barack Obama attended Jimmy Carter’s state funeral on Thursday without his wife, Michelle Obama, although a spokeswoman for the former first lady said she sent her condolences to the Carter family.

"Former First Lady Michelle Obama is not in attendance at President Carter’s National Funeral Service,” Michelle's rep Crystal Carson added to People. “Mrs. Obama sends her thoughts and prayers to the Carter family, and everyone who loved and learned from the remarkable former president."

The handshake happened almost four years to the day when Trump supporters called for Pence's execution during the Jan. 6, 2021, Capitol attack.

Former presidents, dignitaries, celebrities and other notable figures gathered to honor Carter. Biden and first lady Jill Biden sat in the front pew alongside Vice President Kamala Harris and second gentleman Doug Emhoff. The president eulogized Carter, praising his religious faith and character.

The former president will be buried in his hometown of Plains, Georgia, following a private service at the church where he taught Sunday school.