Any substance that is able to hold two surfaces together is called an adhesive. Adhesives do this by flowing into every crack, crevice and cranny of a surface so that air cannot intrude to break the seal; they can be used on paper, glass, nylon, wood, metal, rubber, and fabric. Some adhesives are synthetic while others occur in nature. Synthetic glues are of two distinct groups: thermoplastic and thermosetting adhesives. The thermoplastic adhesives can be softened multiple times by heating, while the thermosetting adhesives undergo an irreversible chemical change and when hardened will not soften when heated. Natural adhesives come from both animals and plants. Beeswax and pitch have been used since ancient times, and Egyptians used animal glue over 3,000 years ago to build furniture. Even papyrus, which was used for paper, was made from flour paste. In liquids such as water, adhesion is demonstrated by a concave, upward curving meniscus and positively raised capillary action.
Cohesion is another kind of bonding that is distinguished from adhesion in that it does not require a bonding agent or adhesive. It is actually the bonding between like molecules on a molecular level. In order for this to happen the two surfaces must be smoothed down to a few microns accuracy so that the two surfaces can bond by molecular attraction and actually become one piece. When metal gauge blocks are put together, they cannot be pulled apart but can be separated only by sliding. In liquids cohesion is demonstrated by surface tension, and in liquids such as mercury by a convex, downward curving meniscus, and by negatively depressed capillary action.
The Bible describes a unique bonding among God's people that is very strong. We are told that this bond is "closer than your own family" (Prov. 18:24, CEV). This closely bonded family of God spans every nationality, race, and culture; the members of the family are drawn together by common belief and faith. Jesus, our elder Brother, has bound us to Himself by an unbreakable bond of love and adoration. Two very special groups of humans in the last days have especially cohesive bonds: one group are the 144,000 who stand on the sea of glass in heaven having harps of gold and the Father's name engraved in their foreheads (Rev. 14:1-5); the other group are those described as not having received the mark of the beast and as "having washed their robes and have the faith of Jesus" Rev. 14:12,13). May we be so honed by life's experiences that we will be cohesively bonded; may we have a permanent, thermosetting seal that will not soften under the heat of adversity. Jesus said that we are to love one another as He has loved us; it is this love that binds our hearts to one another and to the Father. This is "heaven's glue."
