This phrase appears to express the Jain भावना of samatva — equanimity.

Meaning:

• Labha / laba = gain, benefit
• Sue / sukh = happiness, comfort
• Dukhe = sorrow, pain
• Jeeviye = living life
• Marne = death
• Raha = remain, stay steady

Simple arth: A Jain seeker should remain steady and unshaken in gain and loss, happiness and sorrow, life and death.

Jain teaching behind it: This reflects the principle of:

• Samata: balance in all situations
• Vairagya: detachment from worldly dualities
• Ahimsa and shanti: living with inner peace

In short: Do not become proud in gain, do not become weak in loss; remain calm in pleasure and pain, and even in life and death.

If you want, I can also give this in Gujarati, Hindi, or a more exact Prakrit meaning.