Supplication literally means “a request or petition.” In spiritual context, a person who makes supplication humbly presents his requests before God – With an expectation that He will answer them.
Daniel, in the Bible, was prohibited by King Darius not to offer prayer to any deity than himself. Daniel defied the king’s rule and made his supplication to the living God.
Christians are to daily offer their supplications to God in form of thanksgiving and making petition for their needs.
The Bible reference
“Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God.”
(Philippians 4:6 NIV)