JOHANNESBURG (AFP) - South African Paralympian Oscar Pistorius, on trial for killing his model girlfriend last year, has broken a long social networking silence with a series of tweets on love and pain.

The first tweet on Sunday, his first since February, quoted Psalm 34:18: "The Lord is close to the brokenhearted."

The double-amputee sprinter's second tweet was a photo collage of himself with disabled children, including a young girl with artificial legs similar to his running on a track.

The accompanying text reads: "You have the ability to make a difference in someones life (sic). Sometimes it's the simple things you say or do that can make someone feel better or inspire them."

This was followed on Monday by a photograph of what appeared to be a section of text from Holocaust survivor Viktor Frankl's memoir entitled "Man's Search for Meaning".

"I understood how a man who has nothing left in this world still may know bliss, be it only for a brief moment, in the contemplation of his beloved," part of the text read.

Next, he posted a tweet of a poster reading: "Lord, today I ask that you bathe those who live in pain in the river of your healing. Amen."

Pistorius, 27, who has a religious backround, is standing trial for killing Reeva Steenkamp in the early hours of Valentine's Day in 2013. He has told the court in Pretoria that he shot Steenkamp four times through a locked bathroom door in his apartment after mistaking her for an intruder. But prosecutors say he deliberately killed her after an argument.

His tweets triggered an avalanche of reactions, with some wishing the athlete well while others question his sincerity and call him a "murderer".

Since his trial began on March 3, Pistorius has maintained silence outside the courtroom after his last tweet on February 14 which linked to a brief statement expressing his pain on the first anniversary of Steenkamp's death.

His trial is set to resume on August 7 for closing arguments.