To go through entire books of the Bible (or at least chapters), verse by verse, has three primary benefits: (1) it contextualizes verses and passages that are often taken out of context; (2) it advances the whole counsel of God (the “all scripture” concept of what is profitable for the sheep); and (3) it prevents hobby-horsing (it prevents pastors and preachers from focusing upon only (a) what they want to preach and/or (b) only what their hearers want to hear. Simply put, it leads to balance.
Large portions of scripture, even NT scripture, do not directly relate to the “preaching of the cross” — but all such scripture should be taught in light of the preaching of the cross. Remember, it is babes who want, and need, only milk. It is babes who are carnal and are content to walk as such. Strong meat is for those who love the spiritual milk, who understand that it is not only the foundation for the meat but a remaining, vital part of a healthy spiritual diet. However, those desiring to mature, to grow, know that just as it is unseemly and unhealthy for grown people to rely on milk as the sole substance and sustenance of their diet… it is also unhealthy for those desiring to grow, and who are actively growing, to think that milk alone will allow them to do so healthily. We need meat to grow; we need it to mature; we need it to become strong and to prosper. Meat has nutrients that milk alone cannot provide. So though we are to never despise the milk…. woe to those who despise the meat and who cannot see the great and eternal value of it. Sadly, that is the increasing nature of the professing church in our day. May God give us all wisdom, strength, and grace to feast upon His entire word and not just upon the familiar, not just upon that which allows us to feel comfortable, and good about ourselves.